This cartridge sleeve has the same proportions as the NES cartridge sleeve. I prefer to print them in translucent PETG, so I can easily find the games I'm looking for. You can even color code by genre or series. These are great for storage or display, but I swap them out for the original cartridge cases when I take them in my bag, as the sleeve leaves part of the label unprotected.
Post a make if you end up with an awesome cartridge/color combination!