driver's side mirror popped off

Hello, on my way through drive-through restaurant, i side-swiped a pole and my driver's side mirror popped off (2004 1,8 Nissan Sentra, manual power mirror). It doesn't look damaged but there must have been a pin or clip that was lost because I can't put in back in place. Does anyone know how to order such a part, and if it could be easily installed, or should I just pony up the $200 the dealer said i would have to pay to have it fixed.

Thanks for you input

super glue?

They are supposed to clip in place. I fixed mine with liquid nails