Probably several million dollars considering it would have to be a one-off GM prototype. The Chevelle didn't come out until the 64 Model Year.
There is no way to know how much it is worth. Lets look at it this way it is worth however much the buyer is will to pay for it.
how much cost chevelle what?
How much is a vintage 1960 pepsi bottle worth
I wouldn't sell it but if you want to go and have a collector appraise it.
The value of the car really depends on the condition and mileage on it, although NADA suggests that the average 57' Chevelle costs around 6,000 dollars.
$ 1.00
it was worth $36,944.43
in 1964 a chevelle sold for 2800.00$$
all depends on your engine and running gear and if it's a #'s matching car.
How much Is a 1960 holiday 2 worth
It all depends on the shape it's in and what engine and options on it, you need to get it appraised.
how much would an 1960 singer sawing machine sell for