That would be almost enough down for a full length UQ. Would be just perfect for a 3/4 length UQ. 9*750 =6750 cu in.
56.25 (length) *48 (width)=2700
2700*2.5 (baffle depth)=6750
Shorten it a hair or make the quilt trapezoid instead of rectangular and you've got yourself an overstuffed 3/4 UQ.
Or, you could mail it to me and I could come up with something to make out of it. PIF!