Parts such as the Headlight: Ybs67-8 Washer, Spring, Ring, Retaining, Screw, Pan Head, Collar 322215440000 are included in the Xj650 Maxim 1980 (a) Usa Headlight parts fiche.
In this schematic the "Screw, Pan Head (713)" is used most often.
The Washer(6a1) is the lowest priced item on this Headlight schematic.