The most reasonably priced component used on the Vt1100c Shadow 1100 1986 (g) Usa California Steering Stem / Horn is the Screw,cross 5x10.
Some items from this specific schematic: Horn Assy., Bolt,flange,6x12, Cover Joint Box, B/brg N/rad N/com.
The Steering Stem / Horn assembly is constructed from several parts from which the Stem Comp,strg is the most expensive.