With the clearer picture, it definitely looks like the Intermediate stamp to me, Circa 1959-1966. Drumaholic has updated the scale a bit and added new stamps I believe, but to the best of my knowledge this new scale has not been published for the general public. As a result, the 1959-1966 might not accurate any more. Perhaps he will chime in with a definitive opinion.Was it a 20"? If so 1787 is on the medium thin side I would guess.
BosLover, thank you for hanging in there with me to get the info. Very much appreciated.Cool1