I've got 71k on it right now...but the breakage was due to user error. I have a bum ankle that was seriously hurting and my foot slipped off the clutch mid 3rd to 4th shift and I ended up mashing it into 4th gear while screaming in pain like a little girl.WHen I faced this on my 01 Trooper, I did a search on the web and there are a LOT of part sourcers looking to sell you these. If you can find one locally, obviously better especially if you can see the donor car.
If going rebuilt, just make sure it's a place that has a good rep...I went down that road, too, unfortunately. If you're looking to keep this E around, my 2 cents is get yours rebuilt right and be able to forget about it after the pain in the wallet subsides.
BTW, how many miles before you lost this 4th gear?