The Zunow 5cm F1.1 internal mount lens could be used on most Mirrorless cameras using an adapter. Amedeo makes a good one for various mirrorless mount cameras. He also makes them for Leica M-Mount cameras, are rangefinder coupled. He has two series of RF coupled mounts, the Nikon S-Mount uses a straight Cam, the Contax->Leica mount uses an Indexed Cam to correct for the difference in focal length. I believe the Zunow was made in Contax mount and in Nikon mount- best to look for a marking on it. Very rare lens, congratulations.
I've ended up with a nice collection of Nikon RF's and lenses over the years, the S3 and SP being the favorite users- a 50 on the SP and 35 on the S3 being typical. I "fell into" a pair of Nikon M's at an old antique store, user condition, an M, and an M with flash Sync. The M without Sync had a collapsible Sonnar on it: I figured the original owner did not like the Rigid Nikkor 5cm F2 and had missed out on the Collapsible Nikkor. The M with Sync had a 5005 series 5cm F1.4 on it that someone crushed the filter ring to use 39mm filters with it. Straightened it out, but a Series VI adapter on it. $500 for the pair... no complaints.
