My favorite 27” tires are Pasela , Panaracer . They are a few dollars more than Kenda but worth every penny. They are readily available online at various locations , even eBay. Widths like 1”, 1 1/8”, 1 1/4” are usually available. I also have found Michelin Pro Tek tires at REI in stock for $25 each. They tend to run wide after inflated so check for frame clearance. You can run 700c tubes in 27” tires but make sure you get 28-32 wide for the 1 1/4” tires and check valve type. I have bought from Biketiresdirect with good results but there are a few sources.