How's your ukrainian?
http://www.zenitcamera.com/archive/l...dustar-61.html
The ones at the top are for SLRs, some are M42 some are M39, look for Рабочее расстояние: 45,2 мм means back-focus distance, 45mm is slr-sized.

Down the bottom there's a 61L in two variants, then an L/D (Индустар-61Л/Д) 3 from the bottom in black.
The particular version I have is second from the bottom (I'll check the serial number when I get home, I'm pretty sure it's a regular '61', I think it's from the 50s or 60s). The build quality may or may not have been very good on mine, I can't tell because it's been dropped a lot by the looks, focus gets really stiff around 2m then spins freely to MFD.
There's also an L/D at the very bottom, made for the Fed-6 TTL, says something about 1992 but I'm not sure what.

As is the case with most soviet stuff, the underlying designs were good but QC and workmanship varied wildly. It's more than likely that when they changed the designs, they didn't waste anything, maybe they had more bodies than elements at the time of switchover, so maybe there's new-glass in old-bodies or the other way around sometimes?