Here is a PNP of Save South Vietnam! (https://boardgamegeek.com/boardgame/349134/save-south-vietnam) from Fortress Games.
Notes about this PNP: I had to recreated the Rulebook and Player Aid from scratch; so there may be some grammatical errors.
Save South Vietnam! PNP (https://drive.google.com/file/d/1T2o3jgNHFZBaYkuTU8pF_pxChsAkOMNb/view?usp=sharing)
If you enjoy the PNP, buy the game.