The Washer-plain-small,6m is the lowest priced item on this Radiator/fan/coolant Tank schematic.
The Cap,radiator Guard is the most widely applied product in the KZ1300A1 1979 USA CANADA RADIATOR/FAN/COOLANT TANK ( six times ).
Some items from this specific schematic: Washer,8.5x35x2.3, Washer-spring,5mm, Screw-pan Head,6x16, Switch,fan.