Don't know if there is one for your car but, they are all on CD Rom now. Call 1-800 number for Mercedes Benz from your manual. 1-800-For-Merc. I don't remember the number.
Regarding your hinge problem. What the dealer is trying to convey to you is that they only sell the whole assembly not, just the hinge. Go to local hardware store and try to get something that will fit that. You might have to fabricate something but, it is better than $700. Did you try some MB parts stores? Try clicking above at PartsOnline and see if they have it first or can suggest something.