Magic items that add damage.....

[SpottedShroom]

Just to attacks, not spells. They do affect unarmed attacks, though, and will cause them to damage enemies that resist non-magical attacks.

[Kreador Freeaxe]

Just to attacks, not spells. They do affect unarmed attacks, though, and will cause them to damage enemies that resist non-magical attacks.

Which is just the thing for that "monk" wanting to fight his way through some spirits.