I believe you may have misinterpreted the markings a bit. It is probably a dress sporran from the Argyll & Sutherland Highlanders, Of C (?Canada) Regiment.

The J G Stevenson of Glasgow is likely the manufacturer, although I suppose it could be the owners name and billet.

Depending on the condition of the whole and parts of the item it could be worth a couple hundred dollars or more. Your best bet would be to take several pictures of it from different angles and post them here to others to see and comment on. If you need help posting pics on the forum just ask and we can help you get them up.

Nice find.