The choke tower is typically cast into the main body of the carburetor. A notable exception are the Dominator carbs made after 1983, as they come without this choke tower.
But anyway, back to the issue at hand.
On one side of the carb, you may see a fuel line running from float bowl to float bowl. This typically indicates a Holley carb with vacuum secondaries.
www.mortec.com has listings of list numbers for Holley carbs, and also, the Haynes manual for Holley carbs has many of the list numbers, plus all info needed to rebuild any Holley carb back to factory specs.