I had actually ventured the same route as I had that idea for my Vulcan when I was modifying it. It took me a while to find it but I finally did lol
They are pretty high quality and I also have one myself from the build and ended up not using it because it was an idea that i had almost halfway through my project.
You can also cut out the vents on the back panel and make another slot there and just connect it via pcie ribbon or just make it a dedicated vent zone if you have an aftermarket cooler on your card that dumps heat back into your system
Man I am really wanting to get this case again lol
The problem with those I/O expansions is that you will have to weld it together with the rest of the natural frame of your computer as it will not be a picture perfect fit.