8 1/4 Differential desperately wanted

Not sure what you are building, but my son's 1973 4 door Dodge Dart has a 7 1/4 rear. 2.76 sure grip, still going strong behind a 318 with 273 4 barrel intake and carb, 73 340 exhaust manifolds, dual exhaust and a small Mopar Performance camshaft. 100,000+ miles. I also had an early 7 1/4 rear 3.23 sure grip in a 66 Formula S 273 Commando 4 speed that worked fine for 100,000+ miles. All that said, I know where there is an A Body 8 1/4 rear for $300. I could crate it up and ship from SC. Do you want to spend that much and shipping?