Nick,
I believe $6K is probably a very good price. if it checks out. I'm not familiar with EZ's or the dual axle models.
However, Tika, over at Toyota-Campers owns a 1986 model she purchased in 2001 at $6000 but I don't believe it has a dual axle. In her posts, she says she really loves hers. Here is a link if you want to read her experience.
http://autos.groups.yahoo.com/group/toyota...p;charset=UTF-8
Regards,
Jerry