I think the best bet on Identifying a maker would be from the top lever layout. It appears that the TL pivots further back than normal, the forward screw may be the hand pin.I'm not sure if this layout was to allow the gun to be opened at full cock or what! However I expect there is a patent covering this design.It would be interesting to see the action,lever,underbolt arrangement with the stock off. Someone may then be able to identify patentee and thus maker. It's a long shot I realize but worth a try.
