Life Orb Starmie is fine as well. You will less likely need to make switches, although I think it is good practice to try out Choice Specs Starmie, as Choice items actually really forces you to make decisions on switches. While Life Orb makes decisions easier, it also gets fewer KOs while getting itself KO'd faster. A pokemon that you do have access to that will actually fit into Landorus's role defensively is Poison Heal Gliscor @ Toxic Orb. It will require some patience to get a good one in the hidden grottos though. I've tried this Gliscor: Gliscor / Poison Heal / Impish @ Toxic Orb - 252 HP / 4 Attack / 252 Speed - Toxic / Protect / Substitute / Earthquake And it can beat a lot with just toxi-stalling. Of course, it is not the same as Landorus(-T) offensively, but yeah, it's not bad as a replacement if you are willing to get one.