I would be interested in the source of the new bellows as well. This thread made me curious about using my Autographic 3A. I found that using the cap off of a bottle of cologne (1-1/4" tall) as a spacer on top of a 120 roll, works real well. Keeping the film aligned at the bottom of the camera body lines up the numbers on the paper backing perfectly. I fooled with it enough to see that lining up every multiple of 3, keeps the frames spaced well.
I just developed the film I ran through the camera today. The negs are very dense. I have a feeling the shutter speed is well off on the rapid recitlinear. It is an old Kodak ball bearing shutter. I will have to try it with my shutter tester to see.
I also played with an old Zeiss folder that takes 116 film. I used two nickles on top of the 120 spool, and the same 3 frame spacing. It has a glass plate where the film rides, and makes a unique negative with the corners clipped on the rectanglular negative.
This is fun! And to think these camera's were just sitting on a shelf!