thanks Trev
i spent an hour or two rewinding it and also found a lot of voltage loss from the outside contacts across the aluminum rivets to the inside terminals, so fixed that too. But it still let our a pathetic noise, so fitted a modern 6v one inside the body of it. will upset the rivet counters and the sound is a bit unmanly, but it is certainly loud.
cheers
EDIT: i think it is most likely a clearhooter HF80, maybe as per an A65?