I recently purchased a 2000 Mercedes E320, when I put it through the car wash I noticed the plastic cap on the roof antenna had snapped off. The Mercedes dealer wanted $125 to replace it, which seemed a little steep. They would not give a part number, so I am not sure how to at least check for replacement parts that might be considerably less than the prices charged at a dealer.

Does anyone know where I could look... or even what the part is called?