Best place to find them is either Craigslist or Facebook marketplace. When the Bronco Raptor first shipped in my area many sets became available. Took me a good bit to land on an affordable set but finally did. Advantage of Broncos almost always a set of 5 and mine have a slightly different color trim ring, I think goes well with leadfoot. My truck is F150 so I mounted standard KO2 35s and sold the 37s. Down the road going to be rare wheel and hard to find so get them while you can.
There are 2 wheels styles so best to clarify which you want. I see a lot more 35s in my market…