Do you need a weapon permit to purchase a can of mace?

No you don't need a permit for that

Have purchased mace in the past without one . I do not think you need any kind of a concealed weapons license . However I highly recommend not only getting one but going to a class beyond the one for a license . There should be classes for people using mace as a defense against an attacker. Mace can be difficult . Very easy to mace yourself . If wind is blowing or you are to close to the attacker . If someone is super high on drugs it may have no affect. I am not trying to discourage you . I am merely saying do your homework . What ever you decide get good at it and know the law .

I don't think so