What state are you in, and what are your goals?
You cannot use a kit designed for an ITR because the exhaust manifold bolts up differently. You would need a kit designed for a GS-R, but with some custom piping to make it so the Skunk2 manifold fits.
There are no cheap turbo kits. There are junkyard turbo setups you can assemble for cheap, but that's a ghetto solution.
But before we get there, what are your goals?