Hi, Ryan
You can get solid brass 1/4" x 3" standard threaded bolts at your local
Home Depot store, assuming you reside in the U.S. Next to tungsten,
bras is the best spark gap electrode metal that I have come across. You
can also purchase solid brass 3/8"x 12" long theaded rods from the same,
in case you decide to build a larger coil.
Keep on Sparkin'
David