Kudos to whoever designed these.
I must have bought a set of these five years ago, intending to install them "the next time the o-rings gave out". Believe it or not, I haven't needed to replace the o-rings all this time. Storing the boat in my garage with the bailer closed seemed to minimize the stress on the o-rings (not recommended it you store your boat outside). They are still in one piece, though they have lost their elasticity.
Took a little fiddling and watching a couple of videos, but they work perfectly. It's almost like it was designed with the springs from the get go.
I think I've been playing with opening and closing it for five minutes straight.