In the vintage realm, both the REG Thermic and ISOL bidon by Specialites T.A. used a glass lining similar to that found in a traditional Thermos. And while I am not familiar with the particular Schwinn bottle that you describe, I would be willing to bet that it was subcontracted and license manufactured by some entity other than Schwinn themselves, perhaps even by Thermos or one of the other two aforementioned European companies.
Robert "no stones thrown from his glass house" Broderick ...the "Frozen Flatlands" of South Dakota
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I just acquired a Schwinn water bottle that is lined with silvered-glass on the inside like a thermos bottle. I was unaware that thermos bottles were also used for bike water bottles? The bottle has no sip-valve but the top flips open. Marked made in Taiwan and Schwinn script in red over white hard-plastic body. I hesitate to use this for more than display purposes as I have dropped and broken a few thermos(es) this way.
Jack Romans
Sacramento, CA