Thanks. As far as I know and can tell, this one is an original. My Father picked it up in the 1980 time frame at a Gun show. It just lived on his display shelf for 40 years basically until he passed, and has lived above my mantle, until I got the bug to investigate it.
Given the markings, and semi-low serial number I presume it is a 56-56, in the 52 caliber. And yes, I would actually like to shoot it. The bore is a 6 groove rifled bore, and seems pretty clean for the age.
I have started looking at the various centerfire conversion blocks, but don't have one yet. Trying to start slow.