I live in a very small town..our postmaster has me order the supplies for them..he said they won't send them to him at the post office unless they do a certain volume of business each month..but I can order them using my eBay name as a business. So if you only need a few and your post office doesn't carry them you could always donate your excess ones to your post office. I am sure they would take them.
Happy Stitchin' crafty_linda_b