I've never seen a Sonnar (or J-8) with 18 blades: twice the normal number. I suspect this lens was experimentation and assembly practice for Zeiss parts coming into Russia. Somebody decided to really supe things up on this one!
The focus mount is from 1955 through 1960 or so: the earlier tabbed J-8 mounts did not use the three screws for the rear.
The 1952 SN: most likely Zeiss Glass, Zeiss barrel, finished in Russia. I have some "assembly practice" lenses from this period that have a one-off quality, like they were experimenting with making them on their own. Think of lots of parts and optics coming in from Germany after the war and then reverse engineering them. Ultimately: the Russian fixtures were better, but it took some time. I have some 1950 lenses that never worked, someone much later put them into a focus mount- to use them (those generally worked) or to sell them.
If the images are good agreement with the RF: you should get some really good pictures with it. I'm sure it has Zeiss glass in it, from the SN.
I have a 1952 J-12 with 1943 Zeiss serial numbers for the inner barrels. The focus was WAY off when bought, it is now the best J-12 I've ever used.