I wouldn't worry too much about finding the tires. My guess is that michelin will be replacing them with a newer model. LOTS of cars run huge 20's out back these days so no worries.
Plus Pirelli always has the 345/25/20.
Oh and boiler, why do you keep pluging this tire deal and not mention the shop?
btw, Tirerack has them in stock for $405 each.
