Do NPC spellcasters need a component pouch or an arcane focus?

By D&D 5e RAW, is it possible for the BBEG (or any NPC) to cast spells without needing material components? Alternatively, is there any powerful magic item (e.g. a ring or pendant) in the rulebooks that can allow its wielder to cast spells without needing a component pouch or an arcane focus?

In other words, is there any way I can repeal the following rule?

Casting some spells requires particular objects, specified in parentheses in the component entry. A character can use a component pouch or a spellcasting focus (found in chapter 5) in place of the components specified for a spell. … A spellcaster must have a hand free to access a spell’s material components—or to hold a spellcasting focus—but it can be the same hand that he or she uses to perform somatic components. (PHB p. 203)