[Unspoken]

Matching numbers is a plus. So is having the bayonet and cleaning kit included. If not included, use that as a bargaining chip if you're the haggling type.

I own 5 SKSs. For each one I had to rid the bolt/firing pin of cosmoline. Like dean said, shake the bolt, see if the firing pin rattles. If it doesn't, chances are it's caked with gunk. You need to disassemble the bolt and wipe everything down. Or, you can leave the bolt assembled and take a hair dryer to it, which melts away all the cosmo. I prefer the latter method. Works like a charm.

Also, never apply oil to the firing pin.