Chopper, I would suggest perhaps being a little more patient. It has only been 2 days since your original post and a lot of people don't come on the forum EVERY day and so it may take people longer to stumble across your post. Also, the other issue you are up against is that the owners of the older boats are probably not active on the forum and so may never see your post!
Stay positive and something may turn up. There is another thread called 'ebay watch' which people post in if they find a Cherub up on ebay. You may even find your own, as not everyone who owns a knackered old 12 foot boat knows that it is a Cherub.
What is your budget, what sort of boat are you looking for in particular? Keep the faith!