There is a reproduction unit available because it's the same at the 64 GTO factory tach. A lot of US suppliers of Pontiac repro parts have them. Ames Performance is one place that comes to mind.
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1966 Strato Chief 2 door, 427 4 speed, 45,000 original miles
1966 Grande Parisienne, 396 1 of 23 factory air cars