Once a year, Ilford does a special run of odd formats that apparently began as a run of ultra-large format (ULF) sheet film. It has developed into a production of odd rollfilm sizes as well, including 127. Sometime in late winter they will put out a call for orders. You need to be vigilant because they do a really poor job of publicizing it. The cutoff is usually in late spring, and delivery usually happens in September or October. The rollfilm is sold in bulk quantities, so you'd need to roll your own.