Beautiful quilt!
Your estimate of 80 hours is something to go with...times $10-12 for labor is a minimum of $800-960 just for the labor...add in the materials and you are easily in the $1200.00 price range.
I would explain how much you charge per hour, and your estimate for the hours, and the cost of materials to your customer and see what the response is...years ago I charged $10.00/hr for doing any special orders...so asking $12.00 an hour or even more now isn't out of line.