Help needed with Becker Amp for W220

[sandstheman]

I am in need of replacing a Becker amp in my father's 2005 W220, all i have managed to get is the Mercedes Part number, and corresponding Mercedes price for a replacement part. No one seems to be able to tell me which model this part corresponds to...

Does anyone here know where i can find either an equivalent replacement for this part, or anywhere i can find a more reasonably priced supplier.

The part number i have is:

A2208704089

Any information at all would be a great help, cheers