You should try some of the 4x4 shops and see if they have anything that someone didn't want or exchanged. Otherwise the only used one I think your going to find wont have much tread left. Good luck. Oh yeah, you would more than likely be better with a 16 inch rim. More wheel to support the tire means less sidewall flex. When I get my 78 done I found that they make 37 inch BFG All Terrains for a 17 inch wheel. That should work perfect in my case.