Those pumps are cheap at wal-mart (under $10 I think) and the micron filters are only a couple bucks at almost any HBS store.
Aeration stones are a little price for what they are. You can get a fairly cheap one that just fits on to the end of a hose or the nicer ones have a long stainless tube on them so they are easier to get to the bottom of the wort.
Although now that I'm thinking about it you could probably get one like this
and get a piece of stainless tubing from the hardware store that will fit over the barb cheaper than buying one pre-made that way.
Quick check and Morebeer has the whole setup like this for $32.99