I recently purchased a 2000 E320 and the plastic antenna cap on the roof snapped off during it's first carwash. The local dealer (Fletcher Jones of Newport) said this is common and quoted $125 for a replacment, which seemed a bit high to me; however they would not provide a part number, so I am unable to research alternative sources. (BTW, the gentleman ahead of me was also told they would not provide a part number for something he was looking for, so I actually expected it when it was my turn).

I don't even know what it is called, let alone a part number, so I am unable to Google it.

Does anyone know how to identify and research alternative sourcesfor something likethis?