Such a great collection Charlie.
It seems to me that the easy-open jack was never a large sized pattern. All of the oldies I've seen range anywhere from 3" to 3 5/8".
Those 2001 Marbles of mine measure in at 3 3/4" but I never see that kind of size to the vintage ones.
Well, there were easy opener grandaddy/daddy barlows from several companies - usually 5" closed - though you're probably not considering them to be jacks in the classic sense.