Im not sure if the light meter ever worked in the prism viewfinder. I always used my spot meter when using this. Ive never used the roll film back. Ive only ever shot Fuji FP 3000 with this camera. This is a beat up camera with marks and scratches on it.
This camera has traveled almost all lower 48 states and needs to be used. Id recommend a CLD for this gem. The item "Mamiya RB 67 PRO-S 90mm F 3.8 Lens 120 film back Polaroid Back" is in sale since Friday, March 26, 2021. This item is in the category "Cameras & Photo\Film Photography\Film Cameras".
The seller is "the_longboarding_photographer" and is located in Phoenix, Arizona. This item can be shipped to United States.