Yikes, I suspect the metal would be too fatigued to attempt to bend that back and expect it to not crack. I think you're best bet would be to find a used door from a salvage yard and install it.
Did the window break or was it down at the time? If it broke, you might be lucky enough to find a used door already loaded with a window. And if you're really lucky, you might even find one in the correct color.
-Rod