Of all the components used in this assembly the Oil Pump Assy is the most expensive.
Parts such as the Oil Pump: Bolt, Washer Based (4h7), Bolt, Hexagon Socket Head (4h7, Bolt, Grommet, Gear Cover are included in the Xj750m Midnightmaxim 1983 (d) Usa Oil Pump parts fiche.
The most reasonably priced component used on the Xj750m Midnightmaxim 1983 (d) Usa Oil Pump is the Bolt.