I know around here in the Dallas area the mom & pop exhaust places would probably be $140-$220 for a stock type muffler & pipe over the axle and out the rear. If it's as simple as just cutting the existing muffler out & welding up the new one, I's look for $120-$150 (depending on muffler brand). This is for a single in single out setup without chrome tips. If you have a dual out setup, you could probably add $40-$50 more. I's suggest calling up several local shops and get quotes.