You are pretty much looking at replacing the U brace and the ball stud. You could get a longer stud so that if you break one off again you can grab the threaded section sticking through the bottom and twist it out with a plyers. Or you could use a thin cut off wheel on a dremel tool to cut a slot into the threaded end of the ball stud before you screw it into the U brace. Then if you break it off you can stick a small standard tip screw driver into the bottom of the U brace and twist the broken piece out. Don't land your jump like that again.