You can find hole axle assembly off junk yard pretty cheap. Out of Gen 3 01-02 XLS they got 4.90. It's direct swap. Only problem is to find used one with Hybrid LSD like in your current rear axle. Those tend to be more expensive and rare than open diff.

92 SR, 285/75R16 Yoko MT ARB locker GAST compressor AirLift 1000 MM10500 Snorkel custom rear bumper
02 Montero LS died protecting the master
08 PowerWagon (stock!)