I will add that the carb prices follow the car and years they go with prices. 1966-67 carbs are the least expensive, and 70-71 being the most expensive. Rear carbs always bring better than fronts do , more so if they have the correct choke parts. Also a lot of carbs were sold over the counter for years, so the ones with correct date codes bring the best. IMO when they have service replacement dates stamped into them that hurts overall value.
Also you see a lot of ASKING prices I think more so than actual selling prices, but that's my 2 cents worth.
Matt