The most reasonably priced component used on the Xr650r 2003 (3) Australia / Ssw Water Pump is the Washer 7.2x13x1.2.
Some items from this specific schematic: Pump Assy,water, Oil Seal,12x22x5, Bolt,flange,6x32, Seal,mechanical.
With a quantity of two pieces, the Bolt,flange,nshf, is the most used part in the WATER PUMP diagram.