That, or maybe a whole DS. I'm not looking to spend a whole lot of money. (Or I could trade, but I really don't have that much. I have a few 7.2 volt RC car batteries... That's about all I'd trade.)
EDIT: I found the part I need on Ebay for $15.50 shipped, so unless anyone has one for less.
Also, here's a picture. I only need the board to the left, and the antenna that comes off it (which isn't in the picture except for the part that plugs into the DS on the top of the picture.)

EDIT 2: Okay, now I found one for $9 shipped. Might as well lock this thread.