To buy an M1A or build/have one built, that is the question?  Which would you do and why?  Cost appears to be pretty much equal if we're comparing rifles with all GI parts.  I've heard a lot of people talking about buying a Norinco or Polytech and having it upgraded with GI parts.  Yet I've also heard about soft receivers, out of spec forgings, etc.  I guess the best bet would be to find a used Springfield from the early '90s when they used all GI components.  It's all a bit confusing and I admit I'm pretty much an M1A newb.  Your guidance is appreciated.  Thanks.  MJD

All depends on what you want for a end product.

LRB and Poly receivers are both forged, the rest are not.

Depending if you looking for Mostly USGI parts, then you may luck out and find an Old M1a safe queen that someone is selling for around $1000, If not, then your looking at $2000 for a built LRB.

If your going for match rifle, then you can pick up a Used M1a NM safe queen for like $1200.

As for myself, I build NM rifles, so USGI parts are nice, but I will use non USGI parts as long as they are in spec.

Bottom line is if you are going to build, you want a receiver-barrel-bolt combo that are in spec/head spaced correctly, then you can add parts on from there.  Since chrome plated barrels can not be further reamed, installing a barrel may require several bolt to be tried until you find the one that headspeces correctly.  This rules out buying a single bolt (read USGI bolts are spendy as hell right now) and calling it good with the intent to just install the barrel yourself.
Note: you may luck out and find that the head space is too tight, then you could just lap the bolt into the receiver to get the correct headspace.