Soviet Mystery

[sienar]

This looks similar to some Kharkiv designs, especially the gear. But it doesn't match anything I'm familiar with.

source;
https://www.ebay.de/itm/364406085992https://www.ebay.de/itm/364406081163

 

[flateric]

Just a Neman R-10 (KhAI-5)?

 

[igor-mich]

https://ru.wikipedia.org/wiki/Р-10