Some items from this specific schematic: Collar,l=4.7, Washer,6.5x20x1.6, Washer-spring,6mm, Fender-rear,fr.
The most reasonably priced component used on the Kz550h2 Gpz 1983 Usa Canada Fenders is the Bolt-hex,head 8x16.
With eight applications this Washer,6.5x20x1.6 is the most specified part.