...doesn't? How can I purchase one? I just bought a Mercedes SLK and it has a small screen for the stereo.I was wondering why some has big monitor and some has small ones and I wanted to replace it but not sure where to purchase it at besides the actual dealer. Please help

more than likely youre not going to be able to get a factory radio from another place besides having the dealer order it for you..

BUT..you can try to see about swapping out the radio for something aftermarket, i know that replacing it will be expensive even if you do happen to switch it...but a factory replacement radio is going to be expensive as well...especially a mercedes radio