A cheap way to get a big set of transfer punches is to buy one of those ridiculously low-priced "titanium plated" twist drill indexes you see at flea markets, etc. where you get like 64 bits for $10 or so. They's almost useless as drills but they are made of metal and there are a lotta diameters in small increments. They're really not meant to be punches, but sometimes you want a piece of metal dowel of a particular size.