Well, I would suggest Rhyperior or Marowak (I would go with Rhyperior). You see these Pokemon have the ability Lightning Rod, which will protect Staraptor from Electric type moves. Meanwhile, you have these guys using Earthquake, which won't affect Staraptor due to the Flying type. By the way, you need to improve greatly on the Staraptor moveset. I would use: Aerial Ace (no Roost due to Earthquake), Close Combat, Return, Pursuit. Try the Sharp Beak for an item, to help out Aerial Ace.
