Although there are a few guns tentatively attributed to Benjamin Losey of Motts Corner, NY, his commercial barrels are usually found on percussion guns from south-central New York State and Northeast Pennsylvania. According to Frank Sellers, Samuel A Goddard of New York City "imported locks from his factory in England" around the 1858 time period. Your over under gun PROBABLY was made by a small gunmaker in this region. Made from store-bought components, you'll probably never determine the actual maker. But, the long tail on the tang is distinctive on an over under gun and the cheekpiece drops quite low on the stock, so some other collector might help you to better identify this unknown gun builder. Your gun is a mid-level quality, using bolsters instead of the cheaper "drums" to support the percussion nipples. After a careful check-out, it will probably be a good shooter (I've fired MANY similar guns after verifying their integrity)