Thanks for the positive replies guys!
The idea for the soft beads as a stopper for live bait I saw somewhere some time ago, cant remember where, and I improvised from there. I used to use circles punched out of bait foam for the same purposes, and it worked, but it is not as neat. I got both the bait carriers and the beads from Basil Manning, but have seen the beads in other shops as well.
Fritz, if you don't come right with the beads before you go, I should have some that you could go try out.