The Washer,plug,drain 12 is the cheapest item from this partsfiche.
Some items from this specific schematic: O Ring,21.5m/m, O-ring 13x3.0, Gasket,oil Pan (mca), Gasket Kit B (mca).
This GASKET KIT B assembly utilises two O-ring 13x3.0(s) - the highest specified component.