At least in part I believe as an educated guess it is a Golcher based gun. The Golcher family made some parts and assembled a few rifles in the 19th C. Joseph (Jos.) Golcher was a primarily lock-maker in the Philadelphia, PA area c. 1825 to 1860. His locks are ubiquitous and were used by gunmakers across the country but especially "back East."
Keep an eye on my "One Gun A Week" thread.