The Circlip(10w) is the cheapest item from this partsfiche.
In this schematic the "Bolt,socket" is used most often.
Parts such as the Water Pump: Bolt, Small Flange, Circlip(53v), Gear, Impeller Shaft, Gasket, Housing Cover 2 (nas) are included in the Yp250a 2003 5sj5 France 1b5sj-351f2 Water Pump parts fiche.