Aveo heres the VW part number 6R0501541A....you need 2, if you can't put these in yourself find a shop that will install these for you. Keep your axle.
Did you put in new Munroe rear shocks? Because I have already replaced 2 of them for making this noise, and one of them was only installed for 3 weeks from brand new. If you put other shocks in make sure the foam bumper has been put in...it needs that.
I would expect 300 bucks labour to change the bushings (if they are indeed shot) at least with the VW ones they should last you a very long time.