Can't go wrong with an M1A/M14. They're sexy and reliable rifles. As far as price, it all depends on if you're comfortable with it. Prices in general seem to be just now starting to come back down. You could always give it a bit.
Also, a 16" barrel can still reach out and touch something. My AR-10 12" SBR was banging steel at 500 yards at the super secret desert facility a couple years back.