Found this a couple of weeks ago. The front and rear Fly 'classics' are superb and there's a good range of vintage replacements, too.
http://www.ebay.co.uk/itm/Tyres-Fly-512-Fl...=item2c928dbada
http://www.ebay.co.uk/itm/Tyres-Fly-512-Fl...=item2c928dbada