I have the factory 283 two barrel Rochester in my '57, only problem is that it's not a car engine, it's a truck, 4 speed, with factory governor. It might not be what you are looking for.

1957 Chevrolet 5700 LCF 283 SM420 2 speed rear, 1955 IH 300U T/A, 1978 Corvette 350 auto, 1978 Yamaha DT175, 1999 Harley Davidson Softail Fat Boy