Grim Tuesday
Member
If you can find someone who will do it for you, the Pentacon 6 lenses can be machined to be mounted on Pentax 67, which is a relatively reliable camera compared to anything from the eastern bloc. I happened to pick up a Zeiss Jena 180mm Sonnar that had been converted like this and it is one of my finest lenses and I have tried almost all the native Pentax glass, and almost all the western German Hasselblad Zeiss.