TubeNet

There's a used one at Baltimore Brass:

http://www.baltimorebrass.net/tubas.htm#Used%20Tubas


And then there's this one:

viewtopic.php?t=47


And this is what a new one will cost you with a hard case included:

http://www.wwbw.com/Miraphone-Model-184 ... 5803.music