I'd also reccomend KORE. After using add-a-leaves in the past from most of the manufacturers (rancho, fabtech, rough country, JCwhitney, etc), they are all about the same. The roughest riding of all the setups had to be the rough Country set, and the Fabtechs seemed to have the most effort put into them (teflon pads, taper cut, etc). If your set on an add-a-leave and not the KORE mini pak, I'd reccomend Fabtech.
Also, a spring shop is a good place. Our local spring shop (McBride) is usually just as cheap as an aftermarket set up, and sometimes fit better. Get as long of a leaf as you can, and put it under the main leaf for best results.