Violet,
We had the hitch fabricated at our dealer. The receiver is the same size (2"
as we have for the trailer itself, since we also carry the bike rack directly on the car at times, too. Since you already have a set up, you may wish to try or at least investigate what Ken did with having the weld reinforced. You may still decide to do a hitch receiver, but if you can get by with only $50 versus $200....