Parts such as the Water Pump: Bolt, O Ring, Shim(10x18x1), Washer are included in the Vzr1800 Boulevard M109r 2008 (k8) California (e33) Water Pump parts fiche.
The most reasonably priced component used on the Vzr1800 Boulevard M109r 2008 (k8) California (e33) Water Pump is the Screw.
The sub assemblies and components that make up this Water Pump include this Pump Assy,water, the most expensive part.