This is definately not an Executone telephone. I work for Executone from 1969-1980. We had intercom systems, nurse call systems, paging and sound reinforcement systems, and telephone systems. This is an industrial zone paging system, the bottom button is a press to talk button, the top switches were to select various zones to be paged, the bottom switch was an all page switch.
Boy I miss thoses day, Executone was a great company.