Try one made by Wenoka, Deep Sea. It has all of the features you mentioned, plus, I like that it has a sqeeze clip to hold it into the sheath. I don't care much for yanking the knife out of the sheath while fumbling about underwater. And I really don't like having to push hard to get it back into the sheath underwater either.
I don't have the titanium version, but they do offer it.
Here is a link:
http://www.leisurepro.com/Prod/Categ...KSL.html?Hit=1
Happy Diving....