For whatever reason, MBZ does not sell tow hitches nor endorse towing here in the USA. I chalk it up to fear of litigation, since in Europe they'll let you tow your house with a diesel 4-banger!
Depending on what the trailer's tongue and overall weight are (NOT something I know much about), your wagon will pull a good-sized trailer just fine. If I were you, I'd see if you could get capacity info from the German MBZ website. In Europe, you can get a trailer hitch installed at a Benz dealer
