I don't know of anyone that offers a ball bearing kit for the stock turbo... turbonetics and garret gtp38R are the only 2 ball bearing units for our trucks. if you had an older turbonetics ball buster they do offer a ball bearing cartridge for that but still not the stocker..
if you don't want to break the bank an ATS housing and a wicked wheel will eliminate surge. I'm not sure if they will cause more lag or not though.