Why use a brass pin punch? Well, for one brass doesn’t spark, so if you ever need to drive out a pin in a flammable environment, you’d probably want one. Secondly, they are less likely to leave a mark on steel surfaces.
This brass pin punch set by Solid includes a 6″ center punch and pin punches sized 3/32″ x 4-1/4″, 1/8″ x 4-3/4″, 5/32″ x 5″, 3/16″ x 5-1/4″ and 1/4″ x 5-3/4″. It runs about $26 shipped.