I fixed it up good as new with duct tape, hot glue, and rubber bands. But the mirror eventually fell out, and we've been missing it, so I ordered a whole new side mirror online for $26.
Mike had to take the door panel off to install it, but it didn't take very long.
Now we have a shiny new side mirror. It was way more expensive to order it painted, so I just ordered the paintable black.
Now it's unique and will be easier to spot in crowded parking lots. As more pieces fall off, we'll just replace them with black to balance it out. This will very soon be the car that Noah learns to drive in, so if it gets a little scratched and dented in the process, we won't be upset.