MArflex has them and will answer you. They are the same as the current caps for for the 45re and the GT cameras.
I need one too. For the moment I'm using electrical tape
Home made 4x5 P&S::Gaoersi 6x17::90mm f/8 SA::Fujichrome velvia 50 and Ilford fp4, pan f, sfx.
Alexartphotography
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