This is such a great idea.
If you don't have access to these specific dividers, you can make your own out of cardboard, foamboard, wood...etc.
Drink dividers from the grocery store work too.
youtube has lots of good videos for making your own.
I like this one from Just Get It Done Quilts
https://www.youtube.com/watch?v=q5xwfNdInQg
list of more youtube tutorials
https://www.youtube.com/results?sear...rawer+dividers