Do you have a folding room screen you can use? How about folding closet doors that you could repurpose? Anything that you could fold at about a 45* angle will stand upright and you could drap the quilt over it. A piece of wood strapping nailed to the top would keep it from moving. Can you check to see if there are any large folding shutters at the hardware clearance bin? How about an old artist easel? How about the dry erase boards on stands used for lectures? Maybe check free cycle?