You can do it yourself if you are half way decent with a drill/Dremel and dont mind boogering up the break.
All you have to do is grind or drill the weld down enough to get the pin out. Then thread the break off. Threading it off should clean the threads up where the pin was at.
Just seen it. Was going to say, if it was a torx head that was stripped you can sometimes take the next size allen and "negotiate" it out. Or if you have a good assortment of flat heads they can sometimes work.
Liquid wrench and deep creep works better than kroil in our experiences with rusted bolts and stuck pins. If you have a heat gun then try heating up the first 3 inches of barrel