i have a Federal power steering pump (casting #2537955, i think) and can not seem to find a pulley to fit it. i believe that the O.D. of the pulley should be somewhere between 5 & 7". this pump takes a press on style pulley and the shaft diameter looks to be 9/16". the shaft has a threaded hole in the end of it. does anyone know what the correct pulley size is and where i can find one?