Ewing hackle is good material for dries, and is very inexpensive. They even sell "mini-paks" of hackle with ~30 feathers in a package. You can get a hold of them at 1-877-749-1292.
Administrators: as soon as I find an updated email address for Ewing I will send the required email to them cc'ed to you. The only addy I have seems to be out of date. Let me do some rummaging around to see if I can find it....