No wonder it was so inexpensive....that's like a super generic replacement battery right there! lol I couldn't find what brand it was. Can't beat it for the price though!
The one I'll be getting retails for just under 100. (it's actually the 4600, not a 4800)
[HLI-I9300XL] Buy Mugen Power 4600mAh Extended Battery for Samsung Galaxy S3 I9300 / AT&T Samsumg Galaxy S III I747 / Verzion Samsung Galaxy S III I535 with Battery Door
I'm not seeing a wall outlet charger right off hand. (they do have a desk cradle/charger for them) You'll have to search their site a bit more.