The following pics are of an original NOS genuine Ford accessory part number A-18385-A1 "Locking Radiator Cap With Ornament".
This cap is made by Stant Manufacturing. Jarvis was the other original manufacturer and supplier of Quail caps to Ford.
Thanks to eBay seller 'daniel93306' for his permission to show his pics here on Ford Garage!
Wow! What can I say?
Note the shape of the original cap itself, which is different than reproductions.
Also note the original nickel plated finish and great detail.
Note the original 1929 style Allen socket screw and hinge style.
Note the rich detail of the eyes and feathers not found in any of the modern reproductions! Also note that the shape of the top cap and feature lines is different than the 'smooth' reproductions.