Maybe try the fabric shops abroad. I've spoken to a few fabric shops in England where they've commented that they get people buying fabric from America, despite the vast increase in cost for them, as the British shops tend to be running a good year or so late on the fabrics, so it's useful when the fabric has run out in America. I've often seen the same fabric being held by a shop for years on end, especially if they have a low turnover. Be prepared to pay a lot more, however!
If you can't find it, do you need any help in working out how to get around the problem?