Moreover, I had a (rusty rotten) Ikomat too, called 515/2, which had a working Compur shutter (1-1/250, B, T) and a 105/4.5 Tessar lens! I still have the shutter and the lens. Is anybody interested? The lens is uncoated of course, and it has very light traces of fungus that did not clean up (but they are dead, the bastards!)
The Compur is a bit sticky, tried to clean it up but at slow speeds it's still too slow, probably the 70 y old spring should retire.
I always wondered if a lens swap with this tessar and an Ikonta w 105mm Novar lens could work. The focal lengths and lens diameters should be ok, just I don't know if the fitting of a novar is the same. I would expect so - three groups both, and the shutter/diaphragm is between the second and third element in both cases...