Well, how much is a scanner? If it isn't ridiculous, I could probably get one with B-Day greenbacks.
You could probably get one between $100-$200, just don't buy an Epson... We've had to send our back three times to get lame refurbished ones. It's an Epson Photo Rx600 (I think) and was around $200 when we bought it ~4 years ago.
Scanners by themselves (on Amazon) look to be between $60 and $150 for decent ones. I dunno how much the combo printer/scanners are, if you think the printer would be useful you could look into that.
EDIT: We have one of these Brothers, never actually used it for scanning (has to be hooked up to one comp only to scan, and we use it as a network printer), but they're an awesome brand: http://www.amazon.com/Brother-MFC-7340- ... 815&sr=8-1
(The last one we had was 10 years old when we had to get rid of it because toner was too expensive ie we couldn't find it anywhere)
It also sends faxes, copies, and prints in B/W.