The idea here is to come up with something that would have deterred the Indian invasion of December 18, 1961. Not many people will be familiar with this (which should be part of the fun) so here is a breif on the whole situation;
https://en.wikipedia.org/wiki/Annexation_of_Goa
Yes, I know, its wiki. But this article is pretty well-made, if you have something better then please share the link.
So, yes, the situation looks dire for Portugal, but is it unsalvageable? The point that stands out to me is that after 1954, when a couple of tiny enclaves were liberated by "independent" adventurers, Portugal bumped up the militry presence from next to nothing to 8-12,000 men, depending on the source. Then, in 1960, seeing how this was too much to deal with the little insurgencies going on and too little to survive an all-out offensive from India, it was reduced to less than 4,000 with the others being sent to Africa to deal with new uprisings there.
India didn't make it's move until 1961, so perhaps those extra men were making a difference.
The only point to make about the leadership is that Salazar was not just stubborn, but hard-headed, and Hehru was a classic opportunist in regard to this situation. The Portuguese dictator actually demanded that his men fight to the death (and even punished the survivors with they returned), and the Indian Prime Minister needed a victory that was quick, clean and politically juicy.
The Problem; Portugal is not rich, does not have men to spare and as incredible as it sounds.... had made no serious effort to fortify it's Asian outposts since the 1700s. Many of those old forts are still there, but they won't be much help in this situation.
So, what cheap & practical solutions are there to this for 20th century Portugal?
I will throw out a couple of ideas to get the ball rolling-
A little digging revealed something highly improbable; the "battleship" Vasco De Gama, Portugals only battleship and at less than 3,000 tons probably the smallest ship so designated. It was built in 1876 and mounted 2 x 10" guns.... as an ironclad. It must have been a well-loved ship because it was re-built in 1901-02; it was lengthened to accept bigger engines, and re-armed as well as re-armored!
The replacement of the armor amazes me; the original belt sextended all the way up to the main deck and was 9-7 inches think with 10 inches of teak backing. This was replaced with steel that varied from 10-4 inches and extended underwater to the ram bow.
The guns were replaced with 8" Elswick guns, one on either side in sponsons, a 6" gun on the poop-deck and a 75mm on the bow. Three sources give three answers for the tertiary armament, so I will go with the middle one (Janes) and list that as 8 x 47mm.... all guns new in 1902.
This ship spent it's career guarding Lisbon and saw no action other than a breif duel with Portugese artillery during a coupe. The really improbable part is that it surived until 1935. Why? I have no idea, but there it was.... and there was nothing wrong with it's guns. And in the mid-30s it was starting to become obviuos that the world was headed for a dark time, so what if someone had said; "We don't want some enemy cruiser going to Goa what the Emden did to Madras in 1914, let's put somehthing in Goa before the curtain goes up again!"
After all, this was a time when almost anything could still happen, and even the US had secret plans for war with the UK should that weird possibility ever come to pass.
I will try to include the map from the article-

Centrally located on the coast is Mormogao (one of the best harbors in south Asia) and no, I am not locating the ship there. The spit of land just to the north dominates that waterway and the one leading to Panjim, the local Capitol. I intend to park the Vasco in a concrete cradle right at the end of that T-shaped penninsula, sideways. The 8" guns fire to each side, but not very well straight ahead, so leaving one on the ship and dismounting the other for a shore mounting makes sense. I would also leave the 75mm and 3 x 47mm on the ship, cement it in place (there appears to be bedrock right under the sandy bottom in that area) and spread some reinforced concrete over the deck. There will also be space for AA guns, if they are ever made available.
The 6" and 8" guns left over can be mounted ashore at the points of Bardez and Mormugao, mutually supporting each other and with a couple of 47mm to back them up.
In this case, a trio of Frigates will have to think twice about bulling their way in and shooting the place up, which is what did happen.
As for the funding, the Depression was ending or over in post parts of the world, so Public subscription could go a long way, or even cover the whole thing depending on how elaborate or simple you wanted to go. Power for the ship/fort itself came with it. Not the main engines, I have to assume those would be on their last legs. However, every ship comes with a auzilliary, a Scotch bioler in this case is most likely. I doubt that a ship that spent most of it's life moored at the nation's capital would have had much wear & tear on that particular item.
What else?
From the naval side, not much, but Portugal did have a set of 3 x Vickers-Armstrong Submarines from 1935. That is the same year as the Alfonso, the Sloop/Gunboat that was the local flagship. I don't think they would have done much to bloster Portugal's position in NATO back home, but the one in best condition could have been a nice, shadowy presence, helpful in threatening an Indian blockade.
As for the landward side of things...
I just don't know. WIth Angola heating up and Mozambique coming up soon, there does not seem to be much to draw on. However, we could turn to the people of Goa again, in a sneaky sort of way.
Just make gun ownership legal. For all residents, not just the Portugese. After all, Lisbon claimed that Goa was not a Colony, but a part of "metropolitan" Portugal. A ploy, perhaps, but it did make everyone a full citizen. Thousands of guns in civilian hands = instant partisans in all the occupied areas, the ultimate nightmare for any invading army. It would backfire if the people felt they were being mistreated, so Goa's Governor had better make sure he had the people on his side first.
So, that's what I have, anyone else got any bright ideas?
No joke, that's what I would like to see here, ideas being put forth, a little resourcefulness.

EDIT - I would appreciate it if the Usual Suspects refrain from lobbying the Mods to get another thread shut down.This is not strictly Axis but isn't it tiresome to see verything here all about how Germany could have won, over and over again?
Okay, let's spice it up a little; what sort of German or Italian weaponry could Portugal have picked up cheap in 1945? Did they?
If so, what could have been shipped to Goa by 1960?