I'd be willing to help out. Like ordering some and sending them your way or some such. Let me know.
edit
Anyway, if you look at the second link, you can find 5 or 6 of each book for around 5 each (including shipping). Though there are 5 books, which will max out your budget at $4 a piece so you'll have to look around, but its a place to start.
Also, amazon might have a couple.