Hi Anders,
I bought this set in Hong Kong about 3 years ago for next or nothing. From the research I did on the figures back then I came up with SEALs during the Panama Invasion 1989. Here's some examples from that timeframe:
Have not started mine yet, still in the stash, and will be for a while. Be great to see you build and paint this, do keep us informed.
If it's Vietnam your after perhaps this kind of craft is what you would like to do?
http://www.militaryphotos.net/forums/showthread.php?t=64638&page=242
With a plan you could scratch it and convert the figures?
Cheers,
Glen