12A Rebuild
 

I just purchased a 12A which looks to be out of rx2/rx3 by the rotor housings. When cleaning up the front side housing a noticed pitting to the shop of the rotor and around the intake port. Will this be salvageable?

it's really going to come down to how deep they are, but that looks pretty messed up. start looking for replacements.

That looks pretty severe. Well past the "if you can catch your nail in it" threshold.

If you need to use those irons though, they can be lapped. Any machine shop with a surface grinder can perform the operation. Cost might be higher than finding a good iron. But with 12A parts starting to become scarce, it may be worthwhile.