Don't want to discourage you, but if you're looking on making it in high power these days you should go to the AR.
Don't get me wrong, I got my distinguished badge with the M1A, but now days they are as rare as hens teeth in Service Rifle Matches.
You can get a target grade AR for about 1/3 to 1/2 the price of an used M1A.
I got mine in '77 as a standard grade new for $295. I was shooting for the Guard so their Armors converted it to a Super Match on the Governments dime and still shoot it today, but my White Oak AR Service rifle is easier and cheaper to shoot.
I love the M1A/M14, but you just don't see them in the winner's circle now days