A cat back done locally will be at least close to the hooker cat back with the shipping. Exhaust system hawaii does a ok job depending on who does it, there are other shops out there but their work is crappy. You can never beat a aftermarket bolt on cat back system.
I think a custom system locally will cost you around $500+ a hooker is around 3 somthing + shipping. Hooker uses straight through mufflers and the shops here will use chamber mufflers. Big different in the 2.