Some items from this specific schematic: Tube,breather A, Tube C, Clamp D10.5,tube, Seal,air/c.
Of all the components that make up this Air Cleaner (nps503) the Seal, Sub A/clnr has the lowest price.
The Air Cleaner (nps503) assembly is constructed from several parts from which the Case Sub Assy,air is the most expensive.