US Indian Wars Era Marksmanship Badge, Old Guard, Co.A

Original period manufacture. A very fine 19th century marksmanship badge which looks to be made of silver. The suspension bar is engraved 4th Score, with an enameled target on a silver square. The reverse is very nicely engraved 'Old Guard, Co.A'. Perhaps a reference to the US Army's 3rd Infantry Regiment. Might be a National Guard unit as well. In either case the badge is quite nicely done. Measures 28x35 mm.