ZPARTS.COM sells SU carburetors for 240Zs in several states of condition for varying prices. Not all grades of conditon are always in stock. Please send your request for condition required to Used SU Carb Inquiry
1. "Cores" which may bolt on and work or not, with only a mild clean up and adjustment-no guarantees = $150.
2. Dirty but decent condition, bolt-on and 'run' used carbs = $250. per set
3. Very low mileage, cleaned-up, virtually "new" or rebuilt carburetors documented to having been pulled from running car within 1 year of being installed in new or rebuilt condition. - $350-$650.