Your pistol was indeed manufactured in 1940. The eagle/c means police accepted, as Chimney pointed out. With a numbered correct holster, 2 grand would be a good starting point, after all, the condition is 95% easy. If the mags should be numbered ,than you could add an extra 500. Congrats on such a great find.
NOTE: If the grips have any cracks in them, deduct 300 dollars.