Fel-pro 60273 ?

The guy selling the '74 360 carb might be able to help. Looked like to me that there was a base gasket stuck to the bottom of the carb in the pictures. Might ask him if so and if he could measure it.

I could get a rough guess off my car later this weekend, if you need. But it would be a measurement of one still bolted to the intake, not off the car.