Hi Jon -- thanks for posting to History Hub!
I don't see that we have any audiovisual material related to this hearing in our holdings from the House Committee on Interstate and Foreign Commerce in the 91st Congress.
We rarely have video footage in our holdings because the responsibility for filming hearings usually falls to CSPAN and the news media. As such, we usually point researchers to film and television archival repositories, like the UCLA Film and Television Archives or Vanderbilt's Television News Archives.
However since you're looking for video submitted as evidence in a hearing and not video of the hearing itself, I would recommend reaching out to CBS directly. It's possible they maintain a corporate archives.
You may also want to look into the personal paper collections of Members of Congress that served on the committee (and particularly the subcommittee) -- the individuals are listed at the beginning of the published hearing. The best way to find personal paper collections, which are located in archival repositories all over the country, is through the Congressional BioGuide. For example, see the collections listed for Chairman Staggers.
Thank you so much for this very helpful direction, Sarah! (I assume you are the same Sarah who e-mailed me about this about a month back, so thank you for that as well.)