Masking two sided counters

What is the best way to implement a two sided counter which when masked shows a different mask to the non owner depending on which side of the counter is showing ?

For the owner it is simple as the mask image is shown on top of the normal counter image so using a partially transparent image shows the image underneath.
But for the non-owner the image just replaces what is shown regardless of the owner image.

Is there a way to link each Layer to a non owner mask ? Or another way of doing what I want?