What is an "EQ 9626 SA " stamped carb exatly?

RRR,
You are misreading what I said. Never said they were factory carbs, they were replacement carbs made by Carter to replace factory carbs & the 9626 was certified for a 1971 383 engine.
The 9626 had two 'brothers', the 9625 & 9627, the 9625 certified for a 1972 Chevelle 350, the 9627 certified for a 1972 302 Torino.
When F-M bought Carter, the range changed, eg there was a 9635, not sure if there were internal mods. Then came Edel. I have bought Edel AFB carbs from Summit, well aware these & the above models were aftermarket carbs.