I was browsing in my local Office Depot and saw this belt clip. It is not designed for the MotoX obviously, but it is a very snug fit for the MotoX in the Snap Case (by InCase). It is an even tighter fit for the MotoX in the Reveal Case (by Griffin) and the clip presses on the phone buttons (power and volume).
I prefer the Reveal Case so I notched the belt clip to keep it from pressing the phone buttons and provide access to them.I put some heat on the clip and reduced the overall pressure on the phone.
The cut out is pretty rough, but I will clean it up now that I know it works.
I'm pretty happy with this set-up because I have a solid belt clip that works with my preferred case. YMMV