Yes, there is a corollary to the Bodhisattas in the Mahayana tradition in Theravada.

If I understand your question correctly, Zen developed out of the Mahayana tradition. Tibetan tradition is different from both Mahayana and Zen.

Preservation Foundation of Palm Beach was created in 1981.

The web address of the Mariemont Preservation Foundation is: http://www.mariemontpreservation.org

The phone number of the Foundation For Art And Preservation In is: 202-349-3724.