The NYS Firearms Trade (Swinney/Rowe) lists an "H. Persons" in Plattsburg (NY) in 1859. Apparently he had advertised in the Plattsburg Sentinel, Dec. 22, 1859.
No photos of his work are in this book.
The muzzle looks like it was turned for a starter. The hammer appears to be a replacement,
Looks to be in nice condition. With regards to preserving this piece, I would simply lightly oil the metal parts and bore. Overall, the stock looks to be in good condition so there's really nothing to do there other than keep the dust off.