Cudak888s comment sent me looking for brampton headsets..... and there was a NOS one on ebay. Great I thought. The price got above my limit though - someone really wanted it more than I did

But what I did end up buying was a headclip headset:



predictably purchased it just before Randyjawa found his!

I took a gamble on it as it looks like it has the bearing races I need - it's 1inch x 24tpi - I guess I'll find out once it's made the trip from the UK to Australia..... if it doesn't work out I'll be in touch Randyjawa....thanks for looking anyways, headsets must be like buses..... you wait and wait and then two come along at once