Replacement part number?

Your balance, as you said, measures 33". The stamp reads "32 4" which corresponds to SWISCO's "3240" stamp option. You need either an S380-33 or an S385-33 with the 3240 option. I can't tell just from looking, though, so you need to measure and decide. Measure the shoe like the photo below. If it measures 1-3/32", you have a Series 385. For a 1" shoe, go with Series 380.