Rob -
Actually, the new steering wheels sold by moss, ah spares, etc etc., are virtual carbon copies of the original and are quite reasonable in price. Some would say they are better because they use injection molded plastic for the rim on the new wheels, rather than the fragile plasticine lacquers they used on the original. You just need to carefully remove the injection ridge on the rim, and no one would ever know.
If you are sentimental, you can send your steering wheel to Pearlcraft in Australia for a permanent fix, but at ~ AUD 1,000 for a restoration, it is far more cost effective just to buy a new one.