The real audio set from the EWTN server was a recording of their broadcast, so they were free.
"Traditional Latin Mass filmed on Easter Sunday in 1941 at Our Lady of Sorrows church in Chicago. The film presents the ceremonies of the Missa Solemnis or Solemn High Mass in full detail with narration by then-Mgr. Fulton J. Sheen. Celebrated by Rev. J. R. Keane of the Order of Servites (hence the white habits and cowls), the ceremonies are accompanied by a full polyphonic choir, orchestra, and fifty Gregorian Chanters."