Am about to get ahold of a 1981 or 1982 Peugeot UO9, 12 speed, that has a QR front hub but not rear. I see some axle & cone sets on eBay, with axle diameters of 9.5 or 10. Anyone know which? Any other pointers on this conversion? Thank you!

PS: I expect it will have steel rims. I know the tires are 27 inch. I may eventually replace the rims, or the entire wheelset, with new or used 27 inch (or possibly 700?) wheels. But that is down the road a bit.....