Someone asked about YouTube. The video would not get enough views to make monetizing from ad revenue worthwhile. However, YouTube does have a pay-to-view service that would be worthwhile for PE's family to look into. I think the videos should just be uploaded to YouTube since the set is out of print.
The book, however, should not be put on Kindle - it should be made available through a print-on-demand service like Blurb or Lulu. Then a price can be set and any profit would go directly to the family. Also, being a nice old piece of pulp, digital copies will not easily freely circulate. The Youtube videos could link to the book. (The book could sell on Amazon but be printed on demand. However, Amazon will eat any profit - better to sell through Blurb or Lulu.)