Way to create a accessory for a game

Hi, I have a simple game called Whack[[http://play.google.com/store/apps/details?id=br.com.fabiosistemas.whackamole]] .I only want to add a shopScene to make possible to users to buy accessories to make a new look in the characters in the game(in my case, a mole).
But I don’t to create various moles images, with each one using a accessory, I want to create a accessory image separately and then attach it to the mole image when the game runs.
Anyone have a idea how to do that?

Any help will be appreciated.