Im building a Mamiya M645 ( it’s been a while since I owned one ) and would prefer the WLFer finder to the prism one. LMK if you have a clean working one and your price shipped to me. Thanks.
They are rare enough to be more expensive than the cameras themselves. I've toyed around with the idea of making one out of black card and a cheap magnifying lens. I also found that certain types of LCD screen hoods designed for digital cameras work: they are made of rubber with a magnifier on one end.