IMHO you should purchase a new camera and a new housing.
The 3040 is an excellent camera however I would not spend the money on the Ikelite housing. The camera is too far behind the curve and if the camera dies or you flood the housing you will be left with a basically useless housing unless you can find another 3040, 4000, or 4040.
I am using the C4000 which uses the same housing as the 3040. I have two housings and two cameras and use them constantly.
I must warn you on a used PT-010. The part that usually wears out first is the "horseshoe" looking piece of sprung steel on top of the housing that returns the zoom lever to the center position. The shutter control is part of that assembly and the zoom lever must be centered in order for the shutter to work. It's not if it breaks, but when. Of course I use my camera about three times a week and got about two years plus out of that piece of steel. Nevertheless, there is no replacement part for it, or any other parts, other than the main O-ring. Both of my housings have broken zoom lever springs. It does not render the housing inoperable but you have to do some creative inventing to fill the gap that is left between the base of the lever control and the housing or you will have a wobbly lever/shutter control assembly which may cause a leak at that O-ring. I configured
shims from the plastic tops off Costco (Kirkland) yogurt cups. I had to use three shims on one housing and two on the other as the gaps varied slightly. The housings work fine but you have to manually move the zoom lever back to center before taking a photo. Not a big deal or enough reason for me to buy a new camera and housing.
The Oly 7070 as well as the 8080 are discontinued cameras and housings. Take a good look at Canon and Fuji as well as Olympus before making your decision.
Some things to look for:
Don't buy a camera that does not have manual (custom) white balance capability.
Battery type is another factor. Many of the manufacturers have gone back to or stayed with AA bats. They are easy to get and are cheap. The re-chargeables work best.
Be sure the built in strobe functions in the housing if you don't have an external one.
Check the macro mode distances of the different brands and models and if the flash works in those modes.
Will you want to shoot in the RAW mode?
Good luck.