I think Orion-7 sold a "parts kit" that should cover all the breakable stuff. Never heard of a hammer or sear going bad. Bolts yes, extractor, plunger (easy to loose), action spring (shrinks), other springs (ditto). I figure if I break something, I have other toys to play with until I can get parts. In a TEWAWKI, all bets are off, get an AR15 and plenty of freeze dried food.
Dave