Axles yes,.Dont know about housings.
Look in chevy high perf.mag. ads. Lots of places sell replacement parts for 12 bolts.
I called several today looking for 3 series carrier posi units.
OK,Igot up and went and got a mag.
Drive Train Direct---1-888-584-4327
Drive Train Specialests--1800-251-0628
Just a couple.
Rick