Parts such as the E-15: Spring,starting, Bolt,socket,8mm, Washer,thrust37mm, Gear Set,starting are included in the Gl400c Wing 1981 (b) Japan E-15 parts fiche.
The component with the lowest price in the E-15 schematic is the Washer,12m/m.
This part-list fiche shows all the components that make up the Gl400c Wing 1981 (b) Japan E-15 .