Well what stat increasing item? This is obviously for a competitive team of some sort and the only held items that boost special defense (that I’m aware of) is an Eviolite which doesn’t work for obvious reasons and an Assualt vest which would stop him from using dragon dance
The only reason kyurem black got into ubers is 170 attack and it got a speed increasing move aka dd assault vest would prevent that and make me die to literally every super effective physical move