why not go the super cheap route and just do it yourself?? how hard could it be to take the muffler off with a saws-all then buy some metal pipe in the right diameter from pep-boys or whatever, use some clamps to attach it and then throw a tip on the end, job done. Right? seems like that would be the cheapest, plus you would be able to get your hands dirty
I actually did this on my old chevy pick up a few years ago, and I liked the turn out, I just cant bring myself to do it to a brand new car... Eventually I'll have an exhaust shop do it the right way and get it done the way I want