Tig is far better than mig for something like this. If it has been previously repaired by gas welding, mig or brazing, that really doesn't stop a successful Tig repair. The old repair should be ground out first, of course

I don't know if your picture is showing, here is the url: http://i111.photobucket.com/albums/n...opoutcrack.jpg


I don't see the evidence of previous repair, unless it's on the back. That looks like it should be easy to fix, TIG (GTAW) is the way to go. I suppose you might find a really good mig welder that could do it, but there is brass right beside it that might cause problems.