Turbo upgrades

I sell Dodge cars and trucks for a living. I have a lot of people coming to me asking about SRT-4 turbo upgrades. I know they have them, and I know that it's a factory upgrade, which means it's still under warranty after the upgrade, but does anybody know how much they cost? And also where one could do the upgrade? I'd like to know to help me sell these and get them on the street, I'd like to own one myself