Thank you for everyone who posted. I have now got a number of leads to follow. I have just finished the first short film for PFBC to help promote their cause.
Now I am hooked and will be looking into all their archive material and have just found out that Poole Museum do have two short films but as yet will not release them.
here is the link if you are interested and have taken artistic licence with some of the footage.
Poole Flying boat Celebration - YouTube