You should be fine, as long as you bring a couple hyper-potions, revives, and ethers. I beat them with lvl 60 Groudon, lvl 65 Crobat, lvl 41 manectric, lvl 42 Aggron, lvl 60 Blaiziken, and lvl 49 Gyrados. If you haven't battled them before though, battle a few times without wasting potions, revives, etc., to familiarize yourself.