Those are the stock size: 265/70/18. That's still what I'm running for size, though those Crapyears wore out long ago. Currently running Revos in the stock size, but next month it's time for my third set of tires which will be Nitto Terragraps in 285/65/18. Wider than stock, but same diameter. As you can see in my sig, I tow a somewhat heavy trailer and don't want to mess with my gear ratios by increasing or decreasing the diameter.
You'll really like the mini lift. Just a much better stance but you get to keep the nice stock ride quality. I still say it's one of the best bang for the buck mods I've done.