A California king is 72x84 and a standard king is 78x80. I wonder if she measured correctly? It would be worth checking...
Regardless, the quilt will be pretty big if you want it to come down into the frame. 12' (144") is pretty standard for a longarm's width (although a few are bigger, up to 14', and some are smaller), but not all of that width is usable. The quilt could be loaded sideways pretty easily on most frames though, provided the design is such that the longarmer feels comfortable quilting it that way.
The largest I actually quilted on my 12' frame was 120x118.
Last edited by dunster; 12-28-2012 at 10:10 PM.