If you are going to build more than a few units, here is a link on Amazon where they cost about $0.90 ea, plus approx $.60 ea for shipping (12 basket purchase).
http://www.amazon.com/Round-Pots-inc...0599066&sr=8-4
Single unit quantity turns out to be $1.00, but the SAME $7.00 shipping, which is NOT a very good deal. So, it would appear the "crossover" qty is 4 baskets.
http://www.amazon.com/Round-Pots-inc...0599066&sr=8-1
Raybo