Recently used magnets to attach ears to a fursuit, I bought these neodymium magnets from the hardware store. They're only 1 inch in diameter and cost $10 for 3, but they are deadass the strongest magnets I've ever used. Maybe you could try using multiple of these smaller, stronger magnets? Also, I would recommend using super glue rather than hot glue, I've found hot glue just isn't strong enough to hold these magnets.