I have a 2012 2500HD with 265 60 R20 ties and I cant find any tires that will fit except the stock wrangler SRA's. Any suggestions on a leveling kit and tire size? I dont want to lift the truck just level it

I have a 2012 2500HD with 265 60 R20 ties and I cant find any tires that will fit except the stock wrangler SRA's. Any suggestions on a leveling kit and tire size? I dont want to lift the truck just level it