Ring of Ranged Smite
Wondrous item, very rare (requires attunement by a paladin)
While attuned to this ring, spells and class features with the word 'smite' in their name, that require a hit with a melee weapon attack (e.g. divine smite, searing smite), can be used with any weapon attack.
Art Credit:
Ring by Ben Thompson, copyright Blizzard Entertainment