The most reasonably priced component used on the Cx500c Custom 1980 (a) European Direct Sales Rear Cover is the Nut Hex 4mm.
This schematic depicts all components used in the Cx500c Custom 1980 (a) European Direct Sales Rear Cover partslist.
A sample from the products for the Rear Cover include: Bolt,flange,6x32, O Ring 23x2.8, Cap Tappet Hole, Oring,27.5mm.