Wow, if you're going to put a factory locker in it again that deal from Wayne can't be beat. During a week long Moab trip last week a friend of mine broke his rear locker in his Rubi, cost him $800 for the locker and another $300 for the install. If it was me, I would have done an ARB or a Detroit. Both seem stronger than the factory locker.
I've also read that you can put a Rubicon front locker in the rear and that they are stronger due to the fact that they are not a limited slip when unlocked, but I don't know what all is involved in installing a front locker in the rear axle. Might be something to look into if you want to stay with factory lockers.
There is no physical difference between the front and rear locker. Meaning they will both interchange.
I can't lie, I want this thing gone. But I also understand if you don't want the same locker anymore. I ran Rubicon lockers up until I pulled my axles for 60's. I did break it once and I also busted a shaft - reverse order actually - got the new Alloy USA shafts in and during the test drive found the locker was busted. Had I know the locker was bad, I would have upgraded to a 33 spline ARB or Detroit. Instead, I just put another stocker in and ran that one for a while longer without issues.
I really liked the fact it was a LSD when unlocked and a good one at that. I also liked the fact they operated on 5 psi instead of 100 like the ARB's - so quietness was a strong point. For you, all of this is a strong selling point as well as ease to change from one stocker to another - no gear setup needed - swap bearings and actuator and go. With an ARB, you'll have to setup the gears again, put a hole in the diff for the airline, and plug off the sensor and air holes.
For the sensor I use a oil pan drain plug from a 91 Acura. It's the perfect thread length and with a little grinding on the flange (to match the nylon gasket it comes with), it bolts right in place. Then for the air hole, I just weld it up with some nickle rod.