The twelve Xp500 2004 5vu1 Germany 1c5vu-332g2 Hinterrad Bremssattel component parts are all listed in this schematic.
The Bolt(3ef) is the cheapest item from this partsfiche.
Some items from this specific schematic: Disc, Rear Brake 2, Bleed Screw Kit, Boot 2, Support, Pad.