The component with the lowest price in the OIL PUMP XJ550H/J/K schematic is the Screw, Pan Head(3xp).
Check out any of the eighteen Oil Pump Xj550h/j/k components enlisted.
Parts such as the Oil Pump Xj550h/j/k: O-ring (2h7), Screw Pan Head, Circlip(24h), Cover, Pump are included in the Xj550 Seca 1982 (c) Usa Oil Pump Xj550h/j/k parts fiche.