Hi,saw this carb on Gumtree,maybe useful to a Gold Star owner or racing type
£350.00 ONO dont know if that is good or bad,but have not seen many.

http://www.gumtree.com/p/cars-vans-motorbikes/amal-t10-gp2-carburettor-bsa-stamp/1076491669
cheers Rick

email (option): richardholt@rocketmail.com