I added a Mighty Mite P neck, from StewMac, to my jazz bass, great combo.
You could pick up a Squier Jazz cheap, get one of them, and you'd be in buisness.
It's a real nice neck, satin finish, ready for tuners, and drill holes for the body joint. With the Squier, you could use the tuners/bolts etc. off the original neck.
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