You don't say whether you have any preferences in camera system or housing types. I have a Seacam D700 housing body and a D700 to go with it.
The housing has had several modifications that make it much more user friendly. These include a control that pushes either the preview or the function button on the D700. And provides a port lock. There is also a "clutch" that engages or disengages the manual focus gear depending on whether the camera is set to manual focus or auto-focus. These cost over $2000 to add but made the housing and camera much more functional.
New the housing alone cost over $5000. That is about what I would want for the highly modified housing body and the D700 camera body that includes 2 batteries. The housing currently has a 5-pin flash bulkhead fitting.
I also have a Seacam 45-degree viewfinder, a wide port and a few extension rings that could be included in a "package".