Peter Jameson can be seen accompanying Dory Previn on a live performance of "Mythical Kings and Iguanas" included in
Singer-Songwriters at the BBC (series 01) Episode 03.    http://www.bbc.co.uk/programmes/b00v9lhx

This performance of "Mythical Kings" was taken from an Old Grey Whistle Test Concert circa 1977. I do not have inside information, but as far as I know, neither the OGWT or the Singer-Songwriter series is currently scheduled for re-broadcast.