The most reasonably priced component used on the Ks125-a 1975 Usa Canada Oil Tank/side Cover ('74-'75) is the Washer-spring,6mm.
Check out any of the eighteen Oil Tank/side Cover ('74-'75) components enlisted.
Some items from this specific schematic: Pipe,oil, Tank-oil, Grommet,side Cover,rh, Screw-pan Head,6x14.