http://www.rc-monster.com/proddetail.php?prod=battstrap
He has them. See the link above. I'm sure if you wanted longer straps you could just email him when you place your order and he would substitute longer straps.
Check the drop down on the link for the straps in his store. Many lengths to choose from.
The 10" is standard I think. 8" os for the CRT.5 tray and the other lengths are optional lengths.
Honestly, I use the 11" straps on my truggy so I can run a big fat 5s 6000mah pack for long mains. The 10" work, but just barely. The 12" is very comfortable for the bigger pack, but its almost to long on the more normal size packs.