Window balance number on it is 32 5

This looks like a Series 795 Channel Balance, with a 15-195B shoe sold separately. You can swap the 15-195B with the shoe that comes by default with this balance (our 15-195). See the video below.

To know what length to select, measure the metal channel, not including the shoe or screw tab. To know what stamp option to select, since your old stamp is a little odd for this balance type I recommend weighing the window sash. You can then match that exact weight with one of the weight ranges listed alongside each stamp option on the balance shop page.