The lowest price component in this Oil Pump parts-list fiche is the Screw-pan-cros.
Some items from this specific schematic: Pump-assy-oil, Tube,3x5.8x74, Grommet,oil Tube, '0'ring.
The Screw,meter Gear is the most widely applied product in the AR50C2 1984 UNITED KINGDOM GR ST OIL PUMP ( two times ).