So, I spend my one single cabochon on that other pin up picture (posted as cabochon picture ring, check it out) and wondered if stable plastic would work too. And it did :)
Cut out a picture & a piece of stable plastic (mine was the base for butterfly stickers :P) in the same shape.
Put glue on the top of the pic & stick the plastic above.
Now you only need to make the bow and glue that girl on it :)