1960's Wilson Thorp Sporting Goods Football..."The Duke"

[miracleonice80]

Hi all.....I have a few Wilson "The Duke" Thorp Sporting Goods game balls from the 1960's. Is there any way to get the exact year made on these? I know the Wilson football company used a code system for the footballs in the late '60's and '70's, but did they have any codes for the early to mid '60's? I do not see anything on the balls as far as letter codes......Thanks in advance! Tony