A flip-flops model I decided to give away, for FREE!
The model comes with some parameters, located in the Properties menu, in the Tools Shelf (press N in Viewport).
You can change the color of the shoes, and enable the Displacement mode by ticking the Adaptive Subdivisions box. For this to work, enable the Experimental feature of Blender, in the Render Settings.
NOTE : you might need to tweak the Vertex Groups, and/or the geometry of the model to fit your own character's feet.
The file attached is a Blend file.