Labelling Gang Light Switch Cover

Hi, i am having a bit of memento moment with my 6 gang wall switch. Guests are having trouble with them as well. So I am considering labelling them preferably with permanent option.

I googled for a bit, and found that some business offers laser printing or engraving on those light switch cover.

Has anyone tried those? Are they expensive to have only one 6 gang light cover engraved? Any pricing estimated? And anyone know a business doing it in Brisbane?