I think you will need to settle for two medals. What is wrong with that?
I have seen two different JPII medals. One looked better than the other – in one he looked like himself and in the other he looked a bit scary with a tall miter. Both had Our Lady of Chestahova on the other side. I wear it with Our Lady facing outward (because JPII was dedicated to Mary and would rather that she was more and he was less).
And I saw a Blessed Teresa medal. But I didn’t get one.
Hey, there is no problem with getting two different medals for two different saints (both of whom you love). I wear three medals (St. Benedict, Our Lady of Chestahova / JPII, and the Miraculous Medal).