Carburetor rebuilding kits come with a needle and seat assembly.
Exceptions:
(A) Carburetor gaskets sets which contain gaskets only
(B) A very few carbs that have a non-removable seat, but the kit still contains a new needle
(C) Kit manufacturer error
I would suggest you go back to the NAPA store, and ask politely to speak with the manager. Politely ask the manager to order the same kit and open it in your presence.
There are currently only two major manufacturers of carburetor parts in this country; we buy from them both. We have bought rebuilding kits MISSING the needle and seat; and the next kit having an EXTRA. We generally buy needles and seats by the hundred. Of any given hundred, at least 6 will be missing the needle, the seat, the gasket, or the retainer. Welcome to the modern world where many are looking for 5 o'clock, Friday, and payday!
Mistakes happen. Sounds like the NAPA employee with whom you are dealing is new. Any employee that has been around a few weeks would know that the kit should contain the needle and seat; and obtain one for you.
Good luck.
Jon.
