Nimrod
Assume you have checked out all the usual Grumman sites.
Owners club
www.aya.org Grumman forum
www.grumman.net European Grumman flyers
www.grumpygang.org and as you seem to hale from the Bournemouth area
www.echoecho.co.uk The latter is a Grumman group who have operated a AA5 and two 5B's since 1981 and based at EGHH. If in fact you are locally based PM me for a meet up at the local club.