Parts such as the Muffler: Plate, Connector Lh, Lock Washer, Clamp, Gasket,exhaust Pipe (nas) are included in the Gs850g 1979 (n) Usa (e03) Muffler parts fiche.
The Lock Washer is the cheapest item from this partsfiche.
This schematic depicts all components used in the Gs850g 1979 (n) Usa (e03) Muffler partslist.