Replacement Turbo?

After driving my car (2004 Jetta TDI BEW 5 speed) for the last 3 or 4 years with oil leaking from the turbo to the airbox, I am going to replace or have it rebuilt. Any suggestions on which way to go and what Turbo, if that is the way to go?

This is one of those questions that yeilds a search result.
http://www.myturbodiesel.com/wiki/turbo-upgrade-guide-and-part-numbers-for-vw-and-audi-tdi-engine/