I found the Juki 8700 all setup on a frame with speed controller at a quilt shop. These folks used to sell a big heavy monster machine years ago. They are a well respected quilt shop in central Missouri, near Lake of the Ozarks. It also says that the machine has an 11 3/4" throat. Very reasonably priced for the entire setup IMHO.
http://www.nustylequilting.com/quiltingmachines.htm
I would definitely give them or someone like them a call if I were again shopping for a quilting system.