Consider that if Aero even attacks you, you have succeded. It has not and will not get Stealth Rock up. The amount of damage that Lead Aero's EQ does is entirely irrelevant if it does not OHKO because you are up 6-5 and the opponent doesn't have SR, making Raikou entirely threatening later on in the game. Still, for humor's sake... 73.9% - 87.6%. That's Lead Aerodactyl's Earthquake against this Raikou.
CB Azelf is more likely to simply explode on Raikou rather than Zen Headbutt it, but even if it does, it's dealing 74.8% - 88.5%. Also consider that Stealth Rock isn't up, and again, this Raikou is not using Life Orb, so "it's not over until it's over".
In a game where the "critical existence failure" is the rule (performance does not decrease as HP decreases), and Raikou isn't using a Life Orb, Raikou can technically sweep as long as it has at least 1 HP (and sandstorm isn't up), and it still hits like a truck even if it's low on HP. From my testing, even after it's taken some retarded attack, it can still come back later in the game and put the hurt on stuff.