Call IRO, I had a great experience when I ordered from them, I didn't pay any import/duty since it falls under NAFTA. The guys there will do everything possible to keep the price down. The F<R swap requires V8 springs for it to work right, but I havent heard of it being done on a WJ.
North shore, and very possibly IRO, will be cheaper than National and Modern, both of which overcharge just because they can.