I have done this where welding was impractical. I used Devcon Plastic Steel putty. Metal impregnated epoxy. It can be machined, but since you can spread it and shape it close to what you need before it sets, you can get good results with just a file or a small grinding wheel in a Dremel motor tool. Just make sure that the surface you are applying the epoxy to is as clean as it can be so you get a good bond.