I think if there were Dragon Slaying weapons in my world they would be projectiles. Spear, Crossbow or Harpoon most likely, maybe something like a Batista.
To actually stand a chance against a dragon I think you'd need a fairly high level group that is very prepared. This is actually one of the things I've always loved about RM. Dragons will hand your ass to you. In our D&D days we got to the point where we once took two dragons on at once. That was towards the end of our D&D days, because the general consensus around the table was basically: "Seriously? Did we just kill two dragons in one fight? That's kinda pathetic."
I have dragons in my setting, but most of the world will never see one. They will dismiss them as myth's or something that disappeared long ago. The party will interact with them, in one fashion or another, at some point. That's all I'm gonna say about that.
