Not sure how much money is a concern for you since you're considering a turbo setup. But this is what I would do , buy a set of ported 5.3 heads, get a nice mid-range cam like a 224/228R, upgrade your fuel system (if not already done), and get a wet kit from harris speed.
If you do decide to go with a turbo setup though let me know, I know a guy down here that has an almost complete kit he may be willing to sell.