I have had walnut that sounds great and walnut that wasn't worth the time it took to turn the striker. Local grown walnut is great. Walnut I have bought from Illinois was steamed to even the color of the wood. That stuff wasn't worth a flip. If it seems to be fairly dense, it should do well.
A word of caution - Look closely at the grain. If one end of the blank appears to have straighter grain, use that end for the peg portion of the striker. Use the end that has more figure for the thicker, weighted end of the striker. As you turn figured grain down to the thinner diameter, it becomes less stable. With grain that twists and turns, the grain length is shorter (does that make sense) and is much easier to snap.
Good luck.