The Washer(6.5x20x1.6) is the cheapest item from this partsfiche.
The twenty-one Vl800 Boulevard C50 2011 (l1) Usa California Canad (e03 E33 E28) Seat (vl800 E33) component parts are all listed in this schematic.
With four applications this Cushion,seat(40x20x15) is the most specified part.