Mercedes engine wiring harness rebuild
This guy rebuilds harnesses for much cheaper than it would cost to buy a new one. Being a dealer item, I'm sure the harness is quite expensive. If you look around you might be able to find a harness for a decent price, but if not and it were me in your situation I would be tempted to get it rebuilt.
I am a cheapskate however. $900 for a bundle of wires that should have been made out of better material to begin with makes me a bit angry.