Just ordered a set of 27"x-1-1/4" Kenda gumwall tires from Ebay (no affiliation!). The kit also come with two tubes, and rim strips
The price is reasonable for US members, but being Canadian I had to pay shipping charges more than the price of the tire kit. But I cannot find them locally anyway..
Here's the link (remove spaces)
h t t p s: / / w w w .ebay.ca/itm/231441965652