First of all you did great even with the smaller board. Something that might help in the future in a case like this would be to just keep a large sheet of foam core board on hand. Then you could always cut it the size that you would need, a much less expensive option than what that local shop was asking. Another inexpensive option would be to use cardboard cut to size from boxes and covered to be food safe. In any case, Stanley must have been thrilled! You made his dream come true :)
The Garden Baker