Yes, I bought the single outlet one by them. They do have the output to charge the fire hd. The only fault I could find is when it is plugged into the socket it is very hard to remove, because it has such a low flat profile and fits the socket very tightly.
I solved the problem by using heavy waxed thread, the kind that comes with a hand sewing awl for canvas or leather. And made a loop that can be used to pull the charger out of the socket. The charger has a ridge that the heavy thread can be tied around the charger and then a loop anchored to that 180° degrees apart from each other. Hard to explain, but the end result is a finger loop that can be used to remove the charger with ease.
Edit: A lot stores have usb car chargers, maybe not heavy enough output for the fire hd, except for slow charging. I see them at gas station/convenience stores in the racks that sell cell phone stuff.
If you look you may find something that will work for you, before the storm hits. Even the chain stores that handle cell phone accessory's should have something that would work.
Something is better that nothing, and having no options when the battery's start dieing. If days without power is in the cards I would find something locally, it may not be perfect, but when in need.....!