The most expensive part in this assembly is the Cylinder-engine.
On this parts fiche the Ring-snap,18mm is the most specified component.
Parts such as the Cylinder/piston(s): Pin,11x14x12.3, Piston-engine L,o/s 0, Ring-o,79.5mm, Piston-engine,std are included in the En450a6 454ltd 1990 Usa California Canada Cylinder/piston(s) parts fiche.