The Bulb(12v21/5w) is the cheapest item from this partsfiche.
The Rear Combination Lamp (e2, E4, E21, E26) is made up of components including this Lamp Assy, Rear Combination which is the most expensive.
A sample from the products for the Rear Combination Lamp (e2, E4, E21, E26) include: Nut 6mm, Bulb, Gasket (nas), Gasket.