I'd look at salvage yards,I have found like new hitches on trucks that looked like they towed maybe twice with it --most yards sell them for 25-50 bucks and have a lot of them to choose from..
I recently put a reciever hitch on my '82 GMC K2500 (yes,there IS such a thing!) and the frame rails on 73-87 GM trucks are about 32" wide--I had a like new hitch from a later 88 & up style truck that was wider(more like 34") ,I made it work by using 6" channel iron bolted to the bottom of the frame rails to widen them enough for the hitch to bolt onto..some receivers are a "universal" fit and have sliding tubes you can adjust to fit many different trucks,or have brackets that can be bolted on several different ways to fit various makes and models too...