The Bolt(6x50) is the cheapest item from this partsfiche.
This Front Cylinder Head (vl800t E28) diagram displays the required parts for the Vl800c Boulevard C50 2011 (l1) Usa Californ Canada (e03 E33 E28) Front Cylinder Head (vl800t E28).
In this schematic the "Bolt" is used most often.