yeah, go to a shop and have them cut off the stock muffler and clamp on 3 or 4 mufflers they think would create the sound you want, 1 at a time...
start the truck with each new muffler, throw a rev.
buy the 1 that sounds best.... have it welded on.
dont buy a "catback" unless the stock tubing is rusted.... stock is already mandrel bent, adequate sized, and your not gunna outflow it anytime soon unless you have some decent mods on the truck.