Looks like a "Victory" crank. What exactly did you strip? If it's the pedal threads, a helicoil can fix that easily. If it's the extractor threads, you can use drill chuck remover wedges to remove the arm. Installation will still be in the Usual Manner, unless you've chewed up the square taper.

If the extractor threads, how did you manage that? Those arms are self-extracting with a 7mm Allen wrench. The outer ring of the self-extractor is left hand thread, so it's self-tightening when you remove the arm.