[Fully Lost] "If the Mind Is Free", Leonard Nimoy's 1971 documentary on St. Mary's High School in Chicago

My mom attended the highly experimental St. Mary's High School and Center for Learning in the 1970s. The school had a class specifically about viewing and discussing Star Trek, which got Nimoy's attention. Eventually he produced a documentary on the school, which aired on local TV (apparently on 24 Jan 1971, on WMAQ-TV), and may have been partly intended to raise funds for the school. Could a copy of this film still exist anywhere?

Here's some related stuff I found on the Web:

• A writeup about St. Mary's, which mentions the documentary
• Paper archives at UIC about the school
• A Tumblr post showing an ad for the special
• A wiki page about a fan club mentioning that a transcript of the documentary appeared in a zine (which may itself be lost media)