Previous ed.: 1984.
Contents: Pupils' books 1-4
Teacher's books 1-4.
OBNB doesn't sell books, but you may be able to find a copy at one of these websites:
Mastermaths by P. W. Briten. ISBN 0198348401. Published by Oxford University Press in 1997. Publication and catalogue information, links to buy online and reader comments.
obnb.uk is a Good Stuff website.