Try to find a machine shop that's willing to do a good cleanup, magnaflux, and possibly a pressure test to see if the head is a good candidate for rebuilding. If there's no serious damage, do a valve job and mill the head just enough to smooth it out. Don't let anyone persuade you to install "hard valve seats for unleaded gasoline"- - - - - -it's mostly a scare tactic to increase the shop's bottom line. Stainless steel exhaust valves for a small block Chevy V8 are a drop-in fit, and they accomplish the same thing as stellite valve seats at a fraction of the cost.
