Short Answer: You'll be just fine using a tekkeon. All models will provide enough amperage.
Long Answer: Amperage specifications don't work in the way you're describing the question. The specification for your video camera is a
minimum amperage that is needed, so as long the tekkeon is capable of supplying at least 1 A at 5v, it will happily run. It's helpful to use the fire hose analogy when thinking about the relationship between Amperage, Voltage, and Current. I'll probably butcher this but...
Think of Voltage as water pressure within a hose
Think of Amperage as the diameter of the hose.
Think of Current as the total amount of water than can pass through the hose in a given amount of time. Both Voltage and Amperage contribute to total current.
So, let's say you're trying to fill a water tank really fast. There are two ways to do this; increase the water pressure or get a larger diameter fire hose. But what happens if you increase the voltage / pressure too much? Your fire hose becomes almost like a weapon... the pressure can get so high that the stream of water becomes violent, maybe even able to cut things (like a water jet cutter). This is analogous to 'frying' your device - you've increase the pressure/voltage so much and 'boom.' bad things happen.
However, if you wanted to fill up the tank faster you could also do so by increasing the diameter of the hose. A wider hose means more water can flow through (in the same amount of time and at the same pressure), but there's no inherent danger in having a really wide hose because without increasing the pressure, eventually you'll just end up with an enormously wide hose that has nothing more than a trickle of water at the end (because at a certain point, there's not even enough pressure to fill the hose completely). The hose can literally be as wide as possible without any danger of the water coming out too fast or with too much (violet) pressure.
So with your video camera, it's expecting a certain pressure and a hose wide enough to ensure that it can receive enough overall power (current). If you use a battery outputting greater than 5vs, again 'boom.' your camera is going to be fried. In terms of amperage, all the camera cares about is that the available amperage is at least 1 A. You can use a battery rated for 1 A or 5 A and the results will be (more of less) the same.
FYI - USB is spec'ed up to 5 A for devices that need to charge via a usb cable (like an iPad). Most devices that run off of USB need far less amperage and might operate in the .5 A to 1 A range, but a full 5 A is available as needed.
Here's a semi-decent link describing the water hose analogy (probably more accurately than I have). Hopefully this is helpful.
http://science.howstuffworks.com/environmental/energy/question501.htm