Who makes the OEM is also easy, no one! The company is no longer in existance... My shop foreman had that style that you're looking at on his E53 when he had it, was a piece of shit. That one does NOT mimic the OEM hitch at all! The OEM hitch replaces the bumper support and braces itself into the frame, the one you are looking at just bolts to a thin crossmember between the frame rails, with an arm that shoots forward and braces against the rear subframe. After towing his fishing boat with it a couple of times it was twisting the frame and pointing at a downward angle. That is the worse of the aftermarket designs...
Since I can't get an OEM hitch, in the same boat as the rest of us... I spent less money than that and got a hitch thats a
little beter and is closer to mimicing the OEM hitch. But I plan on doing a little metal fab work and replicating the internal braces that the OEM hitch use to spread the load into the frame. Here's the one I got, and where I got it from. Shipping was fast too. And out of the box pictures are possible since I haven't installed it yet.
http://cgi.ebay.com/ebaymotors/00-06...Q5fAccessories