The Screw,tap.,4x12 is the lowest priced item on this Headlight schematic.
Parts such as the Headlight: Bulb (12v5w), Cover Comp., Cord Comp..marker, Bulb,headlight are included in the Cn250 Helix 1991 (m) England Mph Headlight parts fiche.
The most expensive part in this assembly is the Headlight Assy.(1.