Trailer question

I want to build a 4/8 Benroy type TD. I need to have the suspension beefed up for offroad somewhat anyway. I would like to use Torsion axles but I don't weld and if I use a kit trailer.... are there any available with the torsion axles that would take 15" tires? 12 is out of the question for the terrain I have in mind. Anybody know of any company that has one?