I second the MF projector reception (after the above poster of course).
Also, I have a bunch of MF 6x6 plastic mounts but I also have metal ones with glass too, picked up a bunch on eBay for real cheap. Also 35mm of the glass ones.
Anyway look around and keep up the search.
Check goodwill an Salvation Army too.
Mamiya: 7 II, RZ67 Pro II / Canon: 1V, AE-1, 5DmkII / Kodak: No 1 Pocket Autographic, No 1A Pocket Autographic | Sent w/ iPhone using Tapatalk