What cars have the same rear as a Duster?

So a possible fix for now would be to find a set of axles with LBP and change out the bearings? There is a mutitude of problems with this rear right now besides the bolt pattern. The previous owner had installed a set of coil springs on the axle that make an awfull sproing sound going over speed bumps at his school. The car looks great and all eyes are on it so its not cool when it makes that sound. These are in it because the leafs are week and he chose to do this instead of replacing the leafs. We needed more clearance for the large wheels so I put a set of air shocks in it for adjustability. The car bounces badly with all this crap in there but if I remove the coil springs and the air shocks bleed down the tires rub the quarters and thats not good for the paint. The fix is new leafs and a 8 3/4 rear swapped in but the budget is tight and I am finding it hard to find a rear a 17 year old delivering pizza can afford. I paid for everything else on the car for the last four years we have been working on it but the drive train upgrades are on him.