On this parts fiche the Pad Comp,rr(tt) (nas) is the most specified component.
The Rear Brake Caliper is made up of components including this Caliper Assy,rr which is the most expensive.
Parts such as the Rear Brake Caliper: Retainer,rear, Spring,pad, Plate, Caliper Assy,rr are included in the Gl1500 Goldwing 1990 (l) Switzerland Rear Brake Caliper parts fiche.