I know I've seen them for sale somewhere, but apparently my google-fu is weak of late.

All of the plastic tubes I've found so far are chintzy little things that store either beads or coins. I'm quite sure I've seen more industrial types of tubing that you could buy by the foot with as many caps as you wanted. Clear plastic so you can see the bit you're storing, cut to length so you don't have more tube than you need.

Of course, if anyone knows a source for the clicker-type of containers, I certainly wouldn't be opposed.