One that fits both the vehicle AND the wheel.
Seriously - that is about as much assistance as we can provide based on what you've given us to work with - most of the wheels out there use a six bolt hub, some use a five bolt, others use a three bolt - and you haven't told us what vehicle you plan to fit it to.
One more thing, I would strongly suggest that you do NOT get a cheap wood rim steering wheel, if you're ever in an accident you can expect them to splinter, snap & stab you.