Hi Mick
You're on the right track - the ToUcam is still the best budget webcam available.
You can pick up the ToUcam Pro second hand, or the SPC900 / 900nc new or second hand. You might have to look at ebay stores and the like.
Don't forget you'll also need a 1 1/4" adapter and an IR blocking filter. So all up the $200 may be about right.
There's been a few threads discussing ebay stores to get the ToUcam - do a search and see if you can find it, otherwise i'll have a look shortly.
to IceInSpace! Keep asking questions!