http://www.longstonetyres.co.uk/ I've ordered from Longstone in the past. Their inventory is always fresh.
TIRES DEGRADE WGEN EXPOSED TO ULTRAVIOLET LIGHT. THEY ARE DESIGNED TO RENEW THE CARBON AT THE SURFACE (BLACK COLOR) AS THEY TURN DURING DRIVING. IF THEY ARE STORED EVEN UNDER FLUORESCENT LIGHTING THEY WILL DEGRADE AND LOSE THEIR QUALITY AND SAFETY. 10 YEARS WOULD BE TOO LONG FOR ME.