The component with the lowest price in the CARBURETOR PARTS ('81 -'82 KZ750 schematic is the Screw-pan-cros.
The Carburetor Parts ('81 -'82 Kz750 assembly is constructed from several parts from which the Valve,vacuum is the most expensive.
Some items from this specific schematic: Screw,drain, Cap,polyacetal, Main Jet,2nd #122, Washer,plain.