nice find.
i'm not sure re-gear is your biggest challenge with tire size limits. re-gear is not that hard compared to other things that get triggered.
in general, 265/75/16 is biggest on stock and before things get triggered. these are generally referred to as " 31's ", but they are actually almost 32. these are more than an inch taller than what you have now with 265/70/17.
285/75/16 is generally next step up, but things get triggered. these are referred to " 33's ", and actually about 33, usually just shy. but this is where you start to consider a re-gear, because usually to go from 265/75/17 to 285/75/17 you go from P tires to LT, and load rating goes up. this is a lot of extra weight, up to 20# per tire. this is rotating mass, not even in by the wheels, but even further outside the rotation where it's the most penalizing. this is where you really start thinking about a re-gear. 2" lift and proper wheels works for a lot of people to get 285s to fit properly, but if you going to really use those tires for what they were designed for, there are other suspension
and fitment issues.