I don't know whether this set has ever circulated. The Royal Mint, who produced the first set, tell me that it was designed by a Mr David Thomas. I have been unable to find any definitive info on the man, though a piece on numismatic artist
Avril Vaughan states that she studied under a David Thomas. Whether he is the same one, I don't know.
I emailed two artists I found on the web with the same name, but neither was the artist in question.
I particularly like the seven-sided $1 coin, showing the war spirit, Nguzu Nguzu - or Nusu Nusu, according to some versions. It reminds me of the Easter Island moai. I'm also a fan of heptagonal coins in general.