Hi Chris , There is a copy available in New Zealand . from Book Haven ( at $5.50 NZ ) 154a Riddiford Street , Newtown , Wellington 6032 New Zealand
. I found this through a search here
http://www.biblio.com/usedbooksearch.bib just putting your title in .
I am a keen chaser of astro books and this search site is a regular haunt as is
http://www.bookfinder.com/ . Hope this helps,
Len E