From that picture you may have, could have, and probably should have a bunch of stuff wrong with that...
Grind it down CAREFULLY back to flat, use a brand new gasket, and I'd bet it'll be fine. If not, all the bolts have already been loosened one way or another, you'll have fresh never seize compound in there anyhow I'm sure, it won't be near such a chore to get back to where you are for more intrusive corrective actions.
I still bet it's fine though. You aren't the first to be faced with that dilemma.