I see that Brownells is selling M1A receivers (seconds) for $500.
What can a person expect the cost and availability of parts for the rest of the parts, anyone know?

I have some parts like TRW OP rods, gas cylinder + piston, flash suppressors, but pads, stocks. I had a couple boxes, but can't find one box.

CMP sold some M-14 parts kits a few years ago. I haven’t seen any listed recently but you could watch the auction page on the CMP web site or post a want to buy on their forums.

$750 to $1000 for about any kit with used GI issued parts - functional, not pretty, and not near new.

Add 50-100% for decent kit with "as issued" military parts, or with serviceable mix of GI / Commercial hardware with a good stock.

The days of abundant cheap GI rifle kits are behind us - it's going to be cheaper to buy a complete used M1A.

YMMV

You're probably right. $500 for a receiver that an issue with a bolt hole, plus $1,500 or more for parts... Ever since the service I've wanted a M1A. I have a couple M1's maybe I should be happy with what I have.

I have a Springfield Armory M1A and I like the heck out of it. Very nice fit and finish with great looking walnut. I did add some more BLO. So far 100% function. Accuracy as good as I am able to judge with open sights. Or to be specific 2 MOA with cheap practice/bulk ammo. actual target saved are 3 MOA becasue my eyes and iron sights open up the shooting. No doubt with the right ammo and shooter mine is likely a competitive example. Mine was called 'loaded', not stainless match. I considered adding an M14 stock and dummy selector, but; decided this gun was too nice to mess with. And who am I kidding with a fake M14, when I can have a cherry M1A?

I also have two CMP Garands and like those every bit as much. The only issue is bulk/surplus 30-06 ammo is much harder to locate and when found it cost more. Try and find it! I am still working off my stash of 308 (762 whatever). I see lots of 762 whatever on the shelves today.

The very early SA M1A hd some heat treat issue and a couple of club member seem like they will never forget. AFAIK, today the SA is a very well made gun. My point here, no need to drop 2k on a project when you can buy a well made example, over the counter.