I went searching for the TU thermostat housing some time ago also. I wanted at least 2. But I understand why they don't get remade when the inventory is gone.
It is a shame since there are a good number of us who have been in this a while, and we are all older with better incomes. But there are still alot of newer folks or younger folks getting interested in these classics that are still thrifty out of necessity.
And it is also a shame we don't have a following like some the mainstream car (brand/type) clubs that actually could get any products they want developed. But then our SDAC events would be a complete mad house!

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