I got one but it is in a bad state. I need to take it apart, reassemble, and recalibrate. And then work out how to use it.
This is the best resource I have found so far. It is for a different, but similar machine:
http://amet-me.mnsu.edu/UserFilesShared/Equipment_Manuals/TE_110/Rockwell%20Hardness%20Tester.pdf
Does anyone have any information on how to restore these machines?