TTI makes a kit, Jegs sells a kit and TorqueTech sells a kit. I have Torque Tech 3" mandrell bent head pipes on my car. They fit pretty good but required welding.
youll save some money by having someone custom fit a full system. but i almost garuntee it wont be as pretty as ordered pipes. the people at shops bend their own pipes, and it usually never turns out as good as from a manufacturing plant.