I bought a 92 300E and I think the previous owner gave me the wrong radio code?

I went to the dealer and the code they gave me wasn't working either.
Someone suggested I remove the radio and give the serial #. I did that and was wondering if anyone can help me with a radio code or suggest what to do?
Here's the info:
Becker BE 1432
Serial #: P 9704839
Part #: A 002 820 86 86
I will PM the VIN if needed. Any help is much appreciated THANKS!!