Run, don't walk to http://www.badgerairbrush.com and click on the Garage Sale button.
Whoops, just checked the link and it's down at the moment with the note that it will be back up later today or tomorrow. I expect they are starting to run out of airbrushes!
They have the 200-NH on for (IIRC) $18 and the 100LG or Omni 4000 double action on for $26.
If you miss the sale, you can buy the 200-NH for around $46 online at Dixie Art. Bear Air and Badger no longer seem to stock them, which tells me they are going the way of the dodo.
I would buy the 100LG or Omni 4000 myself. In fact I bought one of each!