I don't know if these will display right. If not, I'll be editing the entry.

Between digging in the archives, and help from the CR list, the maker has been found in Japan. BUT, it is still unclear if he's still making rings or not. The main page displays code rather than Japanese (as if that'd help!), but the images are amazing. SO, I understand, are the prices. Think $175 or so per ring. But these are custom made per order, so, according to the deep pocketed collectors, reasonable. Sigh. Anyway...

Check out these tasty photos:

1957 49x36 - perhaps chrome plated steel?
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... [ Stronglight made similar looking 5-pin steel chainrings http://www.velo-pages.com/main.php?g2_itemId=11532 ]

1957 type 49d 5-pin 48x36


105-bis 36t


mod 63/93 50x37


Here's a mod 105/93/63 adapteur. In this case for 42x32 inner rings


More, as we discover more.