I created a portable case for a wireless mouse from Bambu. I made them to be carried in a backpack so as not to damage the mouse.
In the project I used 8 neodymium magnets measuring 6x3mm and glued them with Super Glue. Optionally, you can use felt or something else in the pocket for a spare AA battery to make it less noisy, I put a 3mm thick piece in it. I also taped a piece of ribbon to make it easier to remove the battery.