That's a lot of feet! You could use one of these boxes as it has 48 compartments.
http://www.joann.com/creative-option...9.html#start=1
I have used these for organizing feet for each machine. Make labels for each of the blue dividers. You might check the fishing/tackle departments for a double layered box like this. I use a similar box for sewing tools and it's easy to take to class. These boxes have larger compartments for ruffler foot, etc.
http://www.basspro.com/shop/en/plano...ided-organizer