I have a Croconaw with Hidden Power Flying? Where can I EV train in Gold or Silver or Crystal for Attack ev's because I wanted to make this moveset

Curse, HP: Flying, Earthquake, Rest/Roar/Rock Slide/Hydro Pump

I have a Bayleef that is soon to be a Meganium, and it has Hidden Power Grass, is that better then Razor Leaf and Giga Drain?