Be careful with any third party ones you may find. Apple are licensing the Lightning cable, and it has a chip in it that tells the iDevice it connects to that it is a legit cable. Apparently Apple have the ability to 'turn off' cables by the chip ID in iOS updates.
There are only 3 licensed factories apparently - products by Belkin, Targus and Griffin are the only ones I know of that are licensed (and they are about the same price as the Apple one).
I don't know if you will find a 10' cable, there would be issues with audio and video transfer (Apple say that for the 1m cable they sell).