On this parts fiche the Spring,head La is the most specified component.
Parts such as the Special Market (e18): Bulb(12v45/40w), Screw, Setter,bulb, Button,horn are included in the Gs400e 1978 (c) (e01 E02 E04 E17 E18 E21 E22 E24 E25 E30 E34 E39 Special Market (e18) parts fiche.
Of all the components that make up this Special Market (e18) the Screw has the lowest price.