US sharpshooter
 

I believe as my first nam kit i would like something that is not an M16, so i figured i would be a sniper, now from looking it up my choices boil down to the M21(M14) and the R700, which should i choose ?

I don't believe US GIs used the M700 during Nam. The XM21 wasn't widely distributed. I'd daresay the most common sniper rifle was the M40. They also used M1s, so that's an option.
The M14 is probably a solid choice.

i think i'll just get a bolt action rifle

You are not obligated to be a sniper, you can do a Early GI kit or a Marine grunt kit, They used the M14 for a little while before switching to "Jamming Jenny". M14s were still around the Tet offensive if I remember correctly.

Here a picture taken durin operation Junction City in 1967 :
The soldier is Us Army
http://upload.wikimedia.org/wikipedi...SupplyDrop.jpg

I know it's an old thread but what the hey.
The marines used the m14 rifle for 2 more years when everyone else were transitioning to the M16's. As forr Duffmans post the marines were the only was using the M40 us army were using the XM21 with 3x9 red field scope.