You really don't have too many choices, and unfortunately, the headphone manufacturers just don't hardly make cans in the over $700 league at all (except electrostatics which need a very specialized and expensive amps, and the Sony R10).
Uless you're willing to shell out $3000-$4000 for the Sony R10, you're only option is the Sony CD3000, which are fabulous cans at the $400 mark. Of course the CD3000's may as well be open as they fail to block out any sound at all. For a grand you can get the Sony CD3000 and a nice amp.
Yes, there are some beyers as well, but info on those is relatively scarce.
markl