"best for the money is one you can install yourself. I dont even know if they make one for and XJ, but i would look for one with 2" spacers for the front. Add-a-leaves for the rear are cheaper, but ride rougher than new springs.
oh yeah, buy american."
xxxxx10000000
budget boost will get you an inexpensive 2" that won't look goofy with the 30's, if you want 3" buy a procomp it's middle of the road in price, American made and really good quality. Rubicon express if you can swing it, they make some really good riding lifts