Parts such as the Oil Pump: Nut, Bolt, Grommet, Screw are included in the Rg125c 1987 (h) (e02 E04 E15 E17 E18 E30 E53) Oil Pump parts fiche.
With a quantity of two pieces, the Screw is the most used part in the OIL PUMP diagram.
The Oil Pump assembly is constructed from several parts from which the Pump, Oil is the most expensive.