The sub assemblies and components that make up this Oil Pump include this Oil Pump Assy, the most expensive part.
Parts such as the Oil Pump: Gasket 137131870000 (nas), Hose (439), Bolt, Union (527 Ckd), Holder, Oil Pipe are included in the Cv50l 1984 Riva 50 Oil Pump parts fiche.
The twenty-one Cv50l 1984 Riva 50 Oil Pump component parts are all listed in this schematic.