They are really rare, but if you are lucky, you can drop several at once. For example, I have dropped 66 from a single creature.
Also, killing Sugar Daddy helps a lot. In addition to dropping the equipment, he can drop up to 20 dark chocolate or milk chocolate coins.
The equipment really requires an absurd amount of coins. It is not worth the effort. It is easier to try to drop the equipment from Sugar Daddy, or even buy it from another player.