Get a Jade. They hide in many different places. They are rare, but if you speak with a blacksmith or engineer they might have one or two to spare.
Get a Bolt Charged Bramble. To get one of those, gather 10 Witherbark Totem Sticks from the Witherbark Trolls of the Arathi Highlands. Bring the sticks to the Circle of Outer Binding, a circle of stones in those same highlands. Place the sticks on the center stone in the circle and wait for lightning to strike it. When it does, the Bolt Charged Bramble will be formed.