The component with the lowest price in the OIL FILTER - OIL PUMP schematic is the Washer,plug,drain 12.
Some items from this specific schematic: Clamper Tube, Seat,relief Valve, Gasket,oil Strain (mca), Pump Assy.,oil.
The sub assemblies and components that make up this Oil Filter - Oil Pump include this Pump Assy.,oil, the most expensive part.