Parts such as the Rear Cushion: Spring,rr.cushion, Cushion Assy,rr., Joint Comp,upper, Nut,rr Cushion Up are included in the Cb750k8 Four Canada Rear Cushion parts fiche.
On this parts fiche the Cushion Assy,rr. is the most specified component.
The component with the lowest price in the REAR CUSHION schematic is the Nut,hex.,11mm.