Hello, the following unit can fit your car according to the year and model:
http://www.seicane.com/car-dvd-player-radio-gps-navigation-system-for-2006-2013-mercedes-r280-r300-r320-r350-r500-r63-with-touchscreen-bluetooth-3g-wifi-tv-1080p-c215
We are sorry that your original car’s optic fiber Harmon Kardon system and optic fiber amplifier will not work after installation. You need to use the 3 meter long speaker cable to bypass the optic fiber amplifier located under the main or assistant driver’s seat .
Even if your car’s optic fiber amplifier does not work, the sound quality of the unit is still very good. It has built-in 4*45W amplifier and this amplifier can drive four speakers of your original car (FL, FR, RL, RR).If you need all the speakers work, you can add an amplifier. If you have any questions about installation, you can send us photos about your original car's plugs. Maybe we can make a wiring diagram for your car.
This unit we recommended has CD DVD player, navigation and Bluetooth music streaming function. Could you please send a picture of your car’s dashboard? Then we can check if it fits your car.Thank you.
By
Seicane