The component with the lowest price in the REAR WHEEL (1) schematic is the Nut A,fr.brk.adj..
This schematic depicts all components used in the Pk50m Wallaroo 1992 (n) Portugal / Sel Rear Wheel (1) partslist.
A sample from the products for the Rear Wheel (1) include: Arm Comp,rr Brk, Tire(michelin), Bolt,flange,5x25, Joint A,brake Arm.