Check out this Engine Shop Tech Tip on
Rochester B Identification. Your carb certainly looks like a Rochester B. Once you remove the carb, look at the underside of the throttle body for a stamped number (if none stamped look along the base flange edge for a cast number) and the underside of the main body fuel bowl for a casting number. You can compare your numbers with the ones in the Tech Tip to hopefully ID your carb and get the correct rebuild kit.
My 1948-51 w/1952 Supplement Shop Manual describes what most folks call the "accelerator pump" as the "Pump System". Same thing, just different terminology.
