I've swapped my rear end for a Ford Dana 60 a few years ago, so that should be a little easier to find parts for.
About the only chance I've got on my front brakes is to either scour the salvage yards for 8-lug drums and hope I can get them apart, or convert to newer brakes.
(Or both).
I don't understand why the aftermarket concentrates on the half tons but almost nothing is available for the 3/4 ton.