Motion Tracking w/ another video source?

[Moojangles]

I want to replace the the lenses of my subjects sunglasses with video clips. Is there an easy way to warp the footage to fit into the lens shape? I've tried using things like Corner Pin but i need the whole image to change not just the four corners.

The glasses aren't perfectly square they are rounded. Also i need to track the motion of the glasses. Is After Effects the best choice for this?

thanks,
B

 

[Shooter]

AEFX or Mocha is better for this task