Teresa - huge thanks for pointing me toward Joseph Bentley (Decco Ltd). In the event, I went for the newly launched 'Gardener's Apprentice' fork. Light? Just over 800gm. As you would expect, shorter than a 'grown-up' one, but suits my wife to a tee since she has lost several inches through age.
Arrived today - £20 inc p&p. A truly beautiful piece of craftsmanship. A collector's piece! Nothing like the usual fading, brittle plastic coated nonsense on the right. It is certainly high recommendation for all the other tools they have on the web. And there's a Potato Fork due out next year. Can't wait! = Tim