If you missed it last month , Shield TV Remote is back in stock at Amazon; very scarce accessory since the new boxes were released.

This is the newest model with improved design, controls and backlit buttons (nice upgrade for older Shield TV owners). Can also control soundbar and some TV functions over IR.

Amazon product: NVIDIA Shield Remote; Voice Search, Motion-Activated, Backlit Buttons, Customizable Menu Buttons, and IR Blaster to Control Your TV
Customer Reviews:
Way better than the crappy remote that came with my original shield of a couple of years ago. Hated the touch volume that always lagged and worked inconsistently. And that the key pad lights up when you move it is fantastic when in a darkened room.