Tutorgram educational teaching aid made by ERCA in 70s

Tutorgram was made in 70s-80s by Enrichment Reading Corp. of America. It was a small black plastic "machine" about 4"x8"x8" & used a stylus to select correct answers from punched cards placed on machine. Designed for primary/ elementary students- provided drill for variety of subjects - self-checking. Low-tech by today's standards, but still fun. Have lots of cards but need to find a machine with which to use them. Reasonably priced.