One thing I've learned the hard way is that the vendor names are often confusing and contradictory.
For instance, I still have no clue what the difference is between an iGo and a vGo, other than the fact that the vGo was produced by Kanger. Both are regulated fat battery 808 threaded devices with eGo-style cone threads.
There was also the vGo 801, which had neither the outer cone threads or an 801 connection. Came out in 2010 and quickly disappeared.
The iGo and vGo name has also been used as another name for the Echo by some vendors, which is an 808 flat-topped automatic fat battery.
And this isn't the first time I've seen the iGo name used for a 510, eGo-style device.
It's all confusing as hell but the names probably come from the various Chinese manufacturing plants, which likely talk to each other about as often as most vendors do. Which is to say rarely, if at all.
Honestly, those look like "stealth" model Echo-E's. The cartomizer on top definitely looks like an Echo-E carto. You can get Echo-E batteries from Cropduster901 and Mountain Vapor, though I'm not sure if they have the LEDs on the bottom.