TG,
Regarding your thoughts that your gun (or barrels) may have been made by W. & C. Scott & Son, I copy the results of my research on this question in a thread from last year: (from a Sherman Bell article in the DGJ)
...Scott aggressively marketed his guns outside of Great Britain. Between 1860 and 1886 he made many trips to America to visit firearms dealers to promote Scott guns and organize a network of importers.
...there are probably more Scott guns in this country than those from most other British makers.
...the Scott company would make a gun to a price... The ever practical Americans bought these plain, but very good guns by the thousands.
...Scott made many guns for other makers.
