You guys are great. Thanks for the info. I'm thinking I might just swap in this unbranded-but-new headset I have. I'm planning on selling the thing anyway.
FWIW, I don't notice any brinelling, though the chrome on the outside has become oh-so-slightly pitted.
Seems like a properly-sized o-ring wouldn't be that hard to find--aren't things like this kind of standardized? Couldn't I just find some o-ring/rubber distributor/manufacturer and get something of the proper width and diameter and flexibility from them?
Thanks for the info, though.
BTW, any short info about Tange Levin headsets? Were they just common for the era, or also special in some way?