If you are desperate to get hold of a James Tyler Variax Bass, at the moment your only option is to put in a feature request and ask Line 6 to make one. Hopefully in the future that will happen, but for the time being, you have 4 options.
1. Make a fake JTV-Bass Image (Like I did) and feel happy about it.
2. Buy a used original Variax Bass.
3. Wait for Line 6 to make some JTV Basses (If they decide to do so).
4. Use an existing JTV!.
So If you’re mad, option 1 is for you, and you can be happy ever after. If you’re a little less mad, 2 is a reasonable option, as is 3 if you don’t mind waiting and hoping.
BUT if you’re maybe a guitarist who sometimes want to play a bit of bass, or you’re a bassist who has some spare cash: Option 4 is for you, and you should go here: http://line6.com/community/message/254305 and read Crusty Old Rocker’s great idea to play bass on your JTV 6 string electric guitar. Crusty has also posted some Variax Workbench custom settings files in that same link, so you don’t even need to set it up yourself, you can just load the settings to your JTV, and away you go!