Mirror identification

Looks like you have an early GM fender mount mirror. Late 50's or early 60's Pontiac, Olds, Buick, Chevrolet, Cadillac Definitely a fender mount GM. With a hole someone drilled in to mount. I remember having to adjust my Dads while he sat in the car.
Yup, looks like you are correct! So far closest I have found are these Buick / Oldsmobile mirrors (looks like almost 1:1 to me) but they are out of stock :(

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