I you are handy and have access to a few things you can fix them yourself. drill a small hole the correct size for a sheet metal screw in the center of the dent. then use a slide hammer dent puller in the hole. Now heres where a buddy could be usefull, use a rose bud to heat the whole area of the dent so it almost glows, then hammer the dent out, keep heating hammering tile the dent is out, be careful not to get it too hot! after you are satisfied braze the hole shut, use a #1 or #2 tip and prefluxed brazeing rod ad just enough to close the hole.
Now this will not make it perfect but it will bring save buying a hole new pipe granted you will have a brass colored spot on your pipe if that doesn't bug you other wise cover it up with pipe armor.