Simple system..
Go to your local muffler shop (I recommend independants or Meineke) and have them bend up and install a 2 1/4-2 1/2" system from the stock manifold back to a 'Turbo' style muffler (or whatever Name Brand you like). Nice sound and reliable. Probably can get something like this installed for in the range of $150 to $225 depending on your location.