Brake pads

It is kind of hard to armchair this one, but what I would do is pull the pads off of one side and take them to the parts store and try to match them up that way. Specifically, look at the pads for similarly sized US market Mercedes cars, like the C-class maybe. Chances are, Mercedes has cut a corner here and used the same pads across many vehicles. Most manufacturers do this. I know it is not the definitive answer that you are looking for, but it should get you started.