There are two speeches by Maxwell Newton available at mises.org:

  1. Maxwell Newton, “Federal Reserve: Handmaiden of Tyranny,” presented at the Mises Institute’s first conference, November 16-17, 1983; in Washington, DC. The 30:52 speech is available here.
  2. Maxwell Newton, “A Recent History of the Federal Reserve,” October 27, 1984; in Houston, Texas. The 58:47 speech is available here. (Editor of Economics.org.au’s recommendation, overlaps with previous speech.)

According to this list of the contents of the National Library’s Maxwell Newton papers, Newton also spoke at a 1989 Mises Institute conference. That speech was called, “The enemies of freedom are alive and well in America.” In the second speech he says that the title of his 1984 speech is “The enemies of freedom are alive and well in America.” So, I think the date in the National Library archives should be 1984.

That aforelinked list of Newton papers looks enticing.