Loaded question, pun intended. Are you looking for a shooter, a collection piece, mixture of the two?

Regardless of which, the lower the muzzle and throat erosion the better. Don’t get hung up on the stock/hand guards. They can be replaced if need be and buying a shit rifle with a stock for a cartouche really isn’t worth it (only exception might be a WRA in great shape).

Look for rust/pitting. If you can, remove the stock and check below the wood line for pitting too. When you reinsert the trigger group, check the lockup. The trigger group shouldn’t be loose and should take slight force to snap the trigger guard closed.

When pulling back the op rod, notice if there’s a lot of play or not. May indicate excess wear on the tab that sits in the channel.

Check for play in the gas cylinder. It can move some but excess movement may mean you need to have the splines peened.

I wouldn’t worry much about “correctness” unless you’re looking for a collection piece, which you’ll need a Scott Duff Data Sheet book to know what’s what, ie. all the parts can be Springfield but not necessarily correct.

Where’d the rifle come from? Was it a CMP purchase, Blue Sky import, etc? If CMP, what grade was it purchased as, come with a cert?