Adding to the pot, a Mamiya RZ67 Pro (original) 120 back.
I have a Pro II and enough Pro II backs, this came with an additional Polaroid back I needed for a project and I don't use it. It looks like the light seals are good on the back, the part that attaches to the camera looks like its started to degrade a bit, but it functions fine. I included images, you can see the back part is fine but at the four corners where the film holder part attaches to the back plate, the foam looks not as good, but so far as I can tell its not so important and on my Pro II models the foam is simply missing so I'm guessing it wasn't necessary anyway.
Selling it cheap $48 including shipping or as above I'll trade for things plus an APUG donation will be made by me from some of the profits of the sale.
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