I am trying to get just the muffler that mimics the Roush off-road version made by Borla. Does anyone know the part number for it? Or what series it is in? Or where i can purchase one.

also...

Would just replacing the muffler change the sound signifcantly? Is it worth it to buy a kit or should i just get the muffler and have a shop do the rest? Can i just change the muffler and nothing else?