At a flea market: Chinon CM-4s (PK) with 50 1.9, 28 2.8 and 135 2.8 for $20. All super clean and working perfectly.
I was thinking of reselling it to a basic photo student come Fall, adding whatever a new set of batteries and assurance that it will get them through the semester is worth. Unfortunately it will need some cosmetic surgery first. A previous owner had engraved his name and SS# into the base. I'm not comfortable letting it back into the wild like that.