Harbor Freight sells cheap knock-offs that work pretty well. I get most of my power/air tools from them because they are cheap. I don't use my tools for work so it's hard for me to justify buying top-of-the-line with my wife! This one is a little more expensive than you are looking for but sometimes they have things in store that are even cheaper than online.
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=44506
They are in OK too- not sure how far away you are from the store. Funny thing about Harbor Freight- you can usually ask them if the item you want is going to go on sale soon and usually they do about a week or 2 later! Not sure why that works but it has been my experince.