I have sanded back and covered with helitape for now. As the frame doesn't seem to be rusting inside out and I can see the extent of the damage, I am not too worried about riding it. I don't know whether a repair is feasible, or the frame is now on its last legs.
May you could drill them and then add brass in the holes with a a MAP burner? You could probably ask in the framebuilding thread where people actually know what they are talking about
I have sanded back and covered with helitape for now. As the frame doesn't seem to be rusting inside out and I can see the extent of the damage, I am not too worried about riding it. I don't know whether a repair is feasible, or the frame is now on its last legs.