The stamp you are hoping to hit a home run with was printed in small numbers.
The common stamp with the same design was printed by the billions.
1¢ was the domestic postcard rate in this time frame so literally millions of postcards were sent with the common workhorse stamp.
Personally I have over 100 postcards with the green 1¢ Franklin stamp. Unfortunately the odds aren't 1 out of a hundred.
I grabbed just a small hand full

If someone offered me a quarter each I'd be thrilled.