Changing rear ends but also driveshafts?
Try your local truck shop ask if they have a balancing machine (if they are a WD for spicer and cert for SPL shafts they have a balancing machine) then just ask them to build it all spicer parts. . .
As for who isn't going to try and sneak some china in......some mentioned in this thread will. . .
. If you have a local shop see them and tell them no china ****, if not call whoever and tell them the same thing. . . (that means no neapco parts either they are a china WD with neapco boxes) It's all spicer parts or all Aluminum and then there are only 3 companies making non china parts for AL shafts which if i were you id do AL over stl all day. . .. many added benefits