Long gone. The OE Carter is right about that 625 - 630 cfm area. So a typical performance bolt on was the larger 750 cfm from a HI-PO 383 or 440. The engine can use it well.
If your going to stay with the smaller carb, I would look into what was listed above. I would skip the AFB in favor of the AVS and a few more cfm's though.
Now if I knew if the choke mechanism will connect to my existing set-up
The throttle bracket is a simple bolt on and lines everything up better than trying to tinker with the stock parts of the car and carb. They come in electric chokes. A simple 12v wire and your done. Grounf the e-choke to the houseing or carb itself.
No need for a manual choke cable or the OE bi-meatl spring in the well. The E-choke simply works better, No performance loss.