Final Fantasy X Petrifying Grenade near Macalania Temple?

I went all the way back to Lake Macalania-Crevasse but I found out i cant go back to the Macalania Woods without defeating Seymour the first time. But I really need the Petrifying Grenades to customize a weapon to have StoneStrike ability so that Seymours annoying guards would just die(petrify) on the first hit. Is there any monsters besides the Iguion in Macalania Woods that Rikku can steal Petrifying Grenades from?