The lowest price component in this Clutch parts-list fiche is the Washer,plain, 6mm.
Parts such as the Clutch: Washer,plain, 6mm, Center Comp,clutc, Disk,friction (nas), Bolt,hex 6x25 are included in the Xl100 K0 1974 Usa Clutch parts fiche.
In this schematic the "Disk,clutch Frict (nas)" is used most often.