These came off of a frankenbike Kabuki some time ago, and have been sitting in my parts box ever since. If you have a guess as to what they are, I'd like to hear it! I'm guessing some variety of Dia-Compe but not sure.
The front is marked "SC" and the rear is marked "5583 Japan" and "BS".
Thanks!mystery brakes front.jpgmystery brakes back.jpg