Thanks Dave; have contacted the Round Pond and got some useful info. Also lots of info from Australia.
Thanks also Ditton Dabler. Have been down the Marblehead route some time ago. My current interest in the 10R is to sail a boat with a really useful WL. The idea of the chined hull was to build something really quickly, not necessarily competitive. For example my last MIni40 centre hull only took a few days to knock together.
Will follow up leads on other boats.
I am quite new to 10Rs, so am no authority, but to quote from a Yachts and Yachting article "Any boat can be a 10 rater and several Marbleheads have been successful in the class by conversion with just one larger rig giving 40% extra sail area" so this could offer another avenue to explore. Although not necessarily hard chine, there are lines available for a number of Marbleheads, including Brad Gibson's Indie.
Also PJ Sails offer the hull for their Tension design 10 rater for a not unreasonable £175.
Have a chat with Roy Stevens (roy 'at' grtayton.co.uk), I've currently got his 10r Sonix round the back of my dining table and I know he is looking to sell her - I sailed her in this years nationals the other month and thoroughly enjoyed myself, even won a race which is a miracle for me. Plus the price is very good.