You need to be careful that you don't try to bend the weld or its adjacent "influence" areas. These areas are brittle (i.e. not relatively ductile, or flexible).

My sense is that you MIGHT be able to expand repair the bend, but you need the bending to be limited away from the weld -- OR, even if it is a casting, the "corner" where stresses tend to be concentrated.

I'd tend to take it to rigging shop that knows what it's doing. If you've ever seen a broken boom....