I made this 3ds template that I am using for my next project and wanted to share it so I'm making this thread. I'll post any other resources I make until I'm rank 7.
I scanned my ocarina of time 3d cover for this, measured dimensions with a ruler, and copied it. I re-created everything including the barcode. This is exactly what the template for a nintendo game sold in the americas would look like, or at least pretty close. The icon for the game that appears on the menu goes in the gray rectangle on the spine.
This is an attempt at a more realistic 3d perspective. I took a photo of my 3ds case and modeled this off of that.
These are the symbols on the back of the games that have these features. They can be placed above the warning text.
You can give credit for these if you want, but I'm not too serious about that.