Joachim Kemmer is Gus/Growltiger, Monica Solem is Jellylorum, and Valda Aviks is Griddlebone (Jennyanydots, who doubles as Griddlebone in the Vienna production). The lead Siamese is played by Tumblebrutus (?John Yost).
The raffish crew are Steve Barton (Munkustrap), Valentin Baraian (Mister Mistoffelees), F. Dion Davis (Skimbleshanks), and ?Michael Howe (Tugger).
For Tumblebrutus and Tugger, I don't have definite information as to who is playing them in this recording: names are supplied from the list of the first cast from this date, and will be wrong if there was a cover on for this performance.