For what it's worth, Universal Cycles seems to have a really good selection of 27" tires online and their prices are competitive. I wanted to find some gumwall tires for my World Voyageur and ended up ordering from UC. I received my tires in only two days (they're in OR and I'm just in Seattle, so YMMV). And lest anyone think I'm a shill (honestly, I avoided Bike Forums for a few years because even the most innocuous review of a product or business seemed to be met with accusations that a poster was a shill), I have no connection, formal or otherwise, to Universal Cycles; I was just happy to find a selection of 27" tires for a good price from someplace other than Amazon. Few shops around Seattle have 27" tires in stock.