The most reasonably priced component used on the Cbx550f 1983 (d) E-12 Oil Pump is the Dowel,pin,8x14.
Parts such as the E-12 Oil Pump: Pipe,oil Path, O-ring,11x2.5x4, Bolt,flange, 6x32, Pin,guide,10.9x6 are included in the Cbx550f 1983 (d) E-12 Oil Pump parts fiche.
The most expensive part in this assembly is the Pump Assy.,oil.