Hey Shaun, Thanks for sending the link. Someone else recommended the same switch, and it's exactly what I'm looking for, but the problem is the switch is for 120V and my pump is 220V. I haven't been able to find one of these for 220V.
Surprisingly (and knock on wood), I haven't had problems with the float string hanging up due to icing like I've heard from others. Lapierre said they'd modify the releaser top for me, but I'd just as soon spend the money on a hi/low sensor switch than on an updated float switch.