In my quest to find a replacement for my RD, I bought a couple off ebay. They came off a 650 Honda, I think it was the CX (V twin) version. Anyway same part number as the D.
They were crappy as it turned out, but none the less another source to search for the D (and C?). The after market one I got was rubbish. Finally managed to get hold a NEW base and swap the bits.