First, 'thanks' to everyone who used their own time to help me learn about my SKS and figure out the problem. I learned a lot here and that pushed me to research more on my own.
This afternoon, I got the matching numbered bolt this afternoon. For a few dollars and my troubles, I kept the other bolt that had gone thru Murray's. It was a good deal. The real shiny one on top is the Murray bolt
I then went straight to the range, slipped in the matching bolt, pulled the trigger and bang. Nice but I've been here before. Pulled the trigger and bang...bang again. I felt cautiously good but, after three more shots, I'm zeroing on my target. I wasn't at the range very long but shot 40 rounds and no problems. It's zeroed close enough for government work, for now.
Took the rifle home, cleaned it, gave it the lacquer build-up treatment and changed out firing pins. The Murray pin feels good. It lives!