Housing only (includes instruction manual, but no ports or other accessories): US $1580 (new price $3950).
I also have two 40D camera bodies for sale at $600 each.
Housing is 2 years old, excellent working condition. Never flooded.
If I am successful in posting pictures you will see that there is some black smearing on the inside of the housing next to a drive cable. This is where I accidentally dripped some liquid electrical tape onto it, then tried to wipe it up, while I was installing a cord for remote release (cord has been removed). This is strictly a cosmetic blemish and in no way affects the functioning of the housing. The remote cord was connected through the Ikelite sync plug, which is currently unused, but available for wiring for remote connection or other uses. The housing also has both a Nikonos style plug and an S-6 plug, both of which are wired to the hot shoe. There are two dovetail mounts for strobes. Small drops of water are present on the outer rim (outside the o-ring) in one of the pictures because I had just completed a leak test (it passed).
For what it's worth, this is the exact equipment used to take the whale photos in the October 2009 issue of National Geographic magazine.