James,
That looks to me like a '67 Pontiac GTO Ram Air carburetor, just by the casting numbers. It's a long shot, but what jets and metering rods are currently in it? If ORIGINAL, I will be able to tell you what carburetor number you have there.
Also, for some odd reason, Delco wiped out all known part numbers for these Pontiac carbs, for the key parts. Maybe because they were not available for sale anymore. I don't know. Take care! Ethan