Need Advice on CD Changer

I'm new to this forum, I have owned 2 C Class MBs before, I currently have a 99 E430 sport, I need to get a CD Changer, it looks like an Alpine,  MC31XX and part numbers are confusing.  I think I currently have a MC3198 or MC3110.  What type of changer should I get as a replacement? I don't want to go to the dealer and pay $900.00 for the part.
Thanks,
CT
Sterling, VA