The lowest price component in this Crankshaft/piston(s) parts-list fiche is the Circlip,piston Pin.
Some items from this specific schematic: Sprocket,16t, Bolt,8x45.5, Ring-set-piston, Bushing,#1,brow.
The Crankshaft/piston(s) assembly is constructed from several parts from which the Crankshaft-comp is the most expensive.