This was an amazing find. They are from the "æ˜å’Œ" "showa period" . The "showa" period is from 1926-1989 but these are about 30 years old . These were used in a school.
The stamp is rubber but it is attached to a sponge like base.
This is a unique version of a cherry blossom.
It measures about 2.3 cm wide. The base is "squishy" so you can really push down and get a good image.