I would also like to order the Get Happy TV special! I wish all of her TV performances could be released as a CD compilation. There is a significant amount of songs she sang on TV - rare performances and lost songs that could significantly add to her small body of solo work.
I have VHS that was released in 1996 - "Best of 1969-1970" from the TV show Music Scene. Cass was a guest host, and the tape features a clip of her singing New World Coming.