Here is a breakdown for a two table tournament, T100-base, 20k stacks, with 20x full rebuys. The total set is 650 chips which includes color up chips.
The most I'v hosted with this set is 16 players, 3 rebuys. I don't see using all 40 stacks in the near future but I wanted to make sure that I could should the situation arise.
Please excuse the color differences on the table i started it with excel on my work comp and then finished it at home using LibreOffice.