Red Northerns definately are not restricted to the Jersey Pine Barrens. I've seen pictures of Georgian specimens, which were also quite red.
As for availability, I remember Cherryville used to breed Red Northerns, but I'm not sure if they still do. Í don't even know if they're still in business.
http://www.cherryvillereptiles.com/bull/red.html
-----
I'm Dutch. Somebody shoot me. 

