in my opinion your best bet is to call moser or yukon and buy a set of big bolt axles from them.. they will come with the big bolt pattern, studs installed and axle bearings installed. then just get a set of big bolt drums from any car with a 8 3/4 rear in it . i believe any 8 1/4 rear drum brakes will work too..... if the rear is a standard a-body size then just ask for the a-body big bolt axles and they will take care of you..
you can redrill the small bolt axles and drums and people have done that for years but to me it just leaves too little metal around the studs for my likeing. people did that before anyone offered the actual entire big bolt axle...