I found a paperback copy of this book by Don Charlwood, 103 Sqdn Lancaster navigator for £4. Checked on Abebooks and the only copy is £80. It was published in Australia,Hawthorn Hudson 1991.
It is a sequel to his other book “No Moon Tonight” and wondering if it is rare hence the high prices commanded.

Crecy are selling new copies for a tenner..
http://www.crecy.co.uk/journey-s-into-night