Did you ever find a replacement part? Specifically I'm looking for "Two replacement 1/2" ID O-rings for the Universal PET closure port - BB-CLZ(PET-O4)-SERV(A)" or an equivalent. I'd be happy to buy the authentic replacement, but can't seem seem to find anyone who carries it.
I was going to measure the one I had and order a bag of equivalent o-rings in silicone from McMaster-Carr, but I dropped it down the shower drain instead....
Edit: I'm guessing one of these should work: 9396K25 (nominal 1/2" ID, 11/16" OD) or 9396K208 (nominal 1/2" ID, 3/4" OD). I could just order both, but then I'd be out $20 for 150 O-Rings, at least 50 (probably 100) of which would be useless.
Reason: Possible McMaster-Carr part numbers