I wish I could help. I have a copy of a Prontor repair manual, but it's for later versions. The manual simply says "Whereas former PRONTOR-SVS shutters had ten diaphragm blades, the number of blades has been reduced in the new shutters...." These newer models appear to have all the blades of identical design, and there's no information about the older models.
If it were me, I'd probably start trying different combinations until I found an arrangement that worked smoothly, then button it up and call it done. Not strictly the right way perhaps, but likely good enough for government work.