Wow, just wow. That looks like the coolest thing ever, love the diver's hatch at the bottom, I can imagine going diving in the caribbean from that thing. Here's another site, but these guys offer 'luxury' submarines:
http://www.ussubs.com/
Most of their subs are capable of 300m and I was just comparing the XXI's stats with USSubs' Phoenix 1000...omg(it is $70 million dollars, but common, it's almost as good as Germany's top u-boat of WW2).
http://www.ussubs.com/submarines/phoenix_1000.php3