Does Edelbrock offer a 600-625 AVS-type carb? That would be very close to the Carter AVS the '68-69 383 4-bbl cars came with.

EDIT: They make some different models of the AVS 650... close enough.

What I don't know is if their mechanical-choke version will work with the OEM choke device, or if you'd need to use their electric-choke model (assuming you still want to have a choke).