GTMax Clear Silicone Skin Soft Cover Case for Apple iPod Nano 6th Generation
I spent hours looking for a clear rubber case for my new sixth Gen nano and this one works/fits just fine for me.  The view showed the buttons were covered up, and that is what I wanted.  However, it came with the holes gone, and I very happy that they came that way.  Easier to get to them. I even got a screen cover for it free!