if you dont want to spend much your better off getting your standard turbo's highflowed or looking out for a set of 2nd hand n1's or high flowed standard turbo's. If you look around you can pick up HKS 2530's for around the 3500-4K mark. For brand new roller bearing garrett's your still looking at around 3500-4K all up depending on where you get them anyways.
a T04 would cost a fair bit more as you'd have to get a manifold, external gate, and all associated piping made up.