I have an "early" MS880 in my shed (still has the cast muffler and spring clips like an 088) with a 42" 404 B+C. The P+C are burned up.
Someday I will have to see if the cylinder cleans up, but I don't know what I would use it for other than milling (and my 660s seem to do that pretty well).
Randy already told me to "only" go OEM with the pistons for these saws.
So many projects, so little time, so many hobbies. I did resurrect 2 660s this year but also spent a lot of time reloading ammo (for myself and numerous family members) and we did a major bathroom project at the cabin (not just outhouses anymore!). We actually have a flush toilet now!
And, at 72, the days are just not as long as they used to be! I currently have 16 running saws, so the drive to resurrect another gets put on the back burner.