The Screw,4x20 is the lowest priced item on this Winker (1) schematic.
On this parts fiche the Screw,4x12 is the most specified component.
A sample from the products for the Winker (1) include: Winker Assy L. Rr., Clip,4x70, Screw,4x12, Winker Assy R. Rr..