In this schematic the "Washer,10.5x15x1.5" is used most often.
The lowest price component in this Front Master Cylinder (kz750-b3/ parts-list fiche is the Nut,6mm.
A sample from the products for the Front Master Cylinder (kz750-b3/ include: Cap,front Brk Switch, Cover-seal,brake Pist, Nut,6mm, Bolt,oil,l=23.