I've picked mine up in Dollar Stores, Auto Stores and Wal-Mart. Even found some on a couple of dust brushes I had around the house. They come in different sizes also. Here's a batch I tied up for a fishing trip to the Poconos last week.

P5180057.jpg

The ones on the left side seem to be the "standard" size for most mops, fluorescent orange, gray, chartreuse, gray and yellow. The tan came from a dust brush I had in the house. I also have a maroon one, haven't tied any flies with it. The middle ones are "bass" size, could only find a yellow mop, but was able to color them with permanent marker to get the black and orange. The ones on the right are tied with "mini" mops I picked up in Pep Boys. A gray one and an off-white one. Colors by permanent marker. I did OK with them, caught a bunch of very nice rock bass and a couple of bull bluegill on the "standard" size, chartreuse and fluorescent orange. A 16 inch smallie on a yellow "bass" size and a bunch of smaller rock bass and smaller bluegills and pumpkinseeds on the minis