Are the head bolts for the 94 del sol Si SOHC engine re-usable? I can't seem to source any of them besides the dealer.

Ya know...there is a forum just for Sol's. But anyway, yea they're reuseable as long as you didn't fuck em up.

No, and make sure you use the new updated metal gasket too.

Well you can, but you're not supposed to. You're supposed to replace them whenever you replace the head gasket (or even whenever you take the head off).