type "coaster brake arm" in the search box, and checkmark the "search titles only" box. there's a bunch of solutions.
mostly, you just have to bend it with a couple of wrenches, or a vice and a hammer. it's usually an easy fix. i've done plenty of them.
here's a thread with a custom brake arm so you get the idea...
oh, and it goes "sprocket, isolator, spokes, isolator, moon-shaped clamps..."