The stock is a surplus U.S.G.I. synthetic. Yes, it was made in the 60's. The camo paint job? I recall S.A. Inc. offering a camo'ed stock as an option at one time. S.A. Inc. was not around in the 60's. S.A. Inc. paints U.S.G.I. surplus synthetic stocks and sells that at a huge mark up. The U.S. Armed forces never had a contract for camo'ed M14 stocks regardless of what the seller is implying. The stock has no special value. It was over priced when S.A. Inc. sold it and it is over priced now. U.S.G.I. synthetic stocks can be had for as little as $10.00-$15.00. You can paint it yourself and do a pretty good job. If the paint job on this one is anything like the black painted stocks S.A. Inc. is currently offering, then it is a piece of crap.
Edited to clarify;
McMillan does sell camo'ed synthetic M14 stocks to the U.S. Govt.. However, they are made for accurized sniper and DMR rifles. This isn't one of them.