Yeah, the real French Mod. 58 have become nearly impossible to get, but I just got my first Grand Bois rims from Jan Heine, and they are really really close to the same thing. They are polished aluminum,like the early version of the SC No. 58, and the same weight, and they build up very nicely. Any serious CR rider should consider getting a set. And I put the emphasis on RIDER. These are the rims you can ride every day for anything for years.
Regards, Earle Young Madison, Wisc. Offering espert wheel services for classic and modern bicycles