Not a wise choice to go with a used or new OEM diff if you're going to replace it. Just think, you weren't on it hard and it blew, so what happens if you get on it hard again and it blows again? Another $1000 down the tubes minimum even if you figure you managed to save $400 the first go round it will cost you an extra $600 right there. Go with a quaife. If Terry sells and installs it, I am pretty sure he charges less than BAT or anyone else sells it for. FYI, you can ship a tranny to MI for about $75 UPS.
Rick