I have a Moller 19 1.5x I was about to post up on EBay with a small 52mm +.5 diopter for $900. It is nearly identical in size and weight to the Isco 8.
In good condition. Some scratches on the body and cleaning marks on the rear element but doesn’t look to affect images quality. 24mm rear thread/larger 39mm front thread. I didn’t get a clamp set for it yet or fully test, but in the process. I have too many lenses and not a lot of time, so let me know and I can send more pics if you are interested.