Just break down and buy another one there only like 30$. Make sure when you put it on the two screws on the back are really loose, or you'll break it again.

Get some 5 minute epoxy from a hardware store. Putty type is easiest, paste type is most effective. As long as you don't get it on the part of the paint this part doesn't go on, you have nothing to lose. Know a guy who does bodywork? Ask him to bring over some Bondo.