The 265/65/18 are the exact same size (diameter) as the 265/70/17s, so rubbing/fit issues are likely to be the same. You may have more problem with rubbing the UCA with the taller profile though.
Check this link for tire sizes.
Tire size calculator
I'd guess on the safe side that you'd only get about 1/2" lift out of the springs alone. Why not spend the extra $100 and add spacers at the same time. You'll get the level stance, better looks and less problems with tires, plus your going to have the suspension out anyways. Trust me, you're going to want to do it when you're not happy with the springs alone. Might as well save time and money and do it all at once. (JMHO)