why don't u try glenluce gun room he has a good selection I get all my cartridges there his prices are ok if it is clay cartridges u can get them at burnkettle at auldgirth
I wo uld try a berretta I use a al391 it is 3 inch and also use it for clay shooting I have had it 6 years with no problems as long as you clean it I also shoot the Solway .