Hi Marcus, I went and took some measurements from a 620 spool and they only seem to be about .015 bigger than the size you have given for a 117 spool maybe they are the same spool. Dave
Got a feeling the original Rolleiflex TLR used 117 film giving just 6 exposures a roll but later when that size disappeard many people adapted their cameras to take 620 film (which is of course a thinner spool than 120). Maybe your camera could be adapted to take 620 as these spools (or trimmed down 120 spools) are not too difficult to find. Finding an actual 117 spool would I suspect be extremely difficult.
117 spolls certainly are hard to find!! I was lucky enough to find one in the camera (an Ensign) hence the initial question.
I have managed to file down an empty spool which fits, but haven't quite got the nerve yet to do this with a loaded spool (ie - one with film still on spool).