Be nice if we knew what it says.
I’m going to send this to a friend of mine who was a Russian interpreter in the Navy back in the 1970s. I doubt he remembers enough to give me much though.
Do a search for a book called "drawings from the gulag". Someone who was stationed at the gulags recorded what he saw. Not for the squeamish. Plenty of images posted online.
Drawings from the Gulag by Danzig Baldaev