The lowest price component in this Swing Arm parts-list fiche is the Stpr.,prop.shaft.
In this schematic the "Nut,hex.,10mm" is used most often.
Parts such as the Swing Arm: Swingarm Assy,rea, Nut,hex.,10mm, Oil Seal,27x43x7, Boot,joint are included in the Gl1500c Valkyrie 1997 (v) Switzerland Swing Arm parts fiche.