The lowest price component in this Rear Caliper (an400za L1 E28) parts-list fiche is the Bolt.
This schematic depicts all components used in the An400a Burgman 2011 (l1) Usa (e03) Rear Caliper (an400za L1 E28) partslist.
Some items from this specific schematic: Bolt, Shaft, Pad & Shim Set (nas), Bolt(8x25).