Hi tthrower,
Before you buy a bunch of flies at a very low rate you need to consider the quality of the flies. Sometimes the cheapest flies are just plain cheap and don't last or sit on the water correctly. Sometimes paying a little more than the cheapest results in much better flies. Here is another thread on
discount flies.
I suggest you order a few flies from a couple of places and see how the shipping and the quality of flies are before making a big order.
Frank