Tires for 18" rims are very very expensive, and the choice is limited.

Sell your rims, and buy 16" or 17" rims (offset or not) and you will save money

 

You may be able to pick a smaller size rim up off here for way chaep as for the 18" sahara wheels the tires are hella expensive, IMO I would search for someone getting rid of there 17" Rubi wheels or even 16" X wheels on here. they have the same bolt pattern the only difference is if you choose to stay stock wheel get some spacers when you go wider or you will rub. I opted to get new wheels and 33x12.5 tires and had them installed on my stock suspension here is stock and after lift and here are a few links with in the forum so people are all over the place and you have a wide variety to choose from
Illinoise
https://www.jk-forum.com/forums/jk-wheels-tires-113/5-2007-rubicon-17-wheels-only-66994/
Washington State
https://www.jk-forum.com/forums/jk-wheels-tires-113/wts-2007-rubicon-wheels-tires-wa-state-67136/
Cali
https://www.jk-forum.com/forums/jk-wheels-tires-113/5-stock-255-75r17-tires-17-wheels-67109/
Gerogia
https://www.jk-forum.com/forums/jk-wheels-tires-113/5-alumimum-stock-rims-not-el-chepos-66296/

No Lift 33x12.5


3.5 Clayton and 33x12.5

 

I was talking to Discount tire Direct, General Grabber AT2 - 265/70/18 are $179 shipped to your door.

Check it out.

 

Check out Discount Tire's web site then PM DT's JK Forum rep for a better deal.