Marvel Carb primary nozzle question

Does anyone know what size the orifice opening should be on a primary nozzle P/N 47-739 out of a MA4-5 carb? I think mine has been drilled out, and need to determine what it should be to correct a very rich condition. Do the P/N's on the nozzles give the information needed to determine the orifice size? Also, a source for a used nozzle would be appreciated.
Thanks!
Bill Waters