Need some help repairing a gauntlet dark legacy

[Cuba]

Just like the title says.  Basically I bought an empty cabinet. No screen, but the controls are all there, with all the wiring too.  The game board inside is Gauntlet Dark Legacy.  Im sure there will be a little work to get everything hooked up again, but I noticed right away that there is no hard drive hooked up, its gone.

So im curious as to how I replace it. Will any hard drive do? Do I have to format it a certain way? Do the files have to be in a certain format?  Is there a legal way to obtain the files I need, meaning if I contact midway is there a way to purchase the files? (I am NOT requesting files, simply imformation.)

Thank you in advance.