Follow-up for anyone interested:
Found this company, they sell on ebay as well:
American Volt
Bought and installed one 160 F and one 180 F fan switch in the radiator. For the first time since I got the car (four years), I can cruise for hours, idle at red lights etc, with no cooling issues whatsoever. Weird that it can take so long to get it right, since that is pretty much like it was designed from the beginning..?
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