Just an update...
It’s actually a .43 caliber. The same estate turned up a set of moulds, about 800 .429 round balls and a note saying to use .018” bed ticking, 55 grains of FFF and a No. 12 cap.
I was told that H. J. Wood lived in Northville Michigan, was well known locally and rifled the barrels himself. I haven’t been able to find out anything else. It’s a shot in the dark, but I’m hoping someone here has a little more info on the maker.