Where can I find a 2x2 hinge on Bricklink?
This is not a LEGO part. It's closest LEGO cousin would be 3149:



3149-like hinges don't have a 2x2 version to the best of my knowledge. In addition, the part in the picture appears to be 12 ldu (1.5 plates) thick. This leads me to believe that it is actually a Tyco part.

Also, it looks like this has already been discussed on Eurobricks where the same conclusion was drawn. From that thread: