Yep, they work pretty well in a CJ, only a few inches wider than the "wide track" CJ axles. I'd expect there's not a huge market though, since you have to move the rear pads and outboard the fronts. The offset rear is good for the earlier models with the Dana 18. $400 seems like a lot though... especially since they are usually 3.54:1 or 3.31:1 and such ratios aren't very desirble. I'd be very pleased to get half that much.
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS, hubcaps.
Browless and proud: '82 J20 360/T18/NP208/3.73, KOs, 7600 GVWR
Copper Polly: '75 CJ-6, 304/T15, PS, BFG KM2s, soft top
GTI without the badges: '95 VW Golf Sport 2000cc 2D