www.arizonadriveline.com
they sell the staked U-joints. you'll need to press out the old ones and press these new ones in. really a bitch and a half, but if you are really wanting to keep your shaft, then this place can help you. just be really careful and not ruin the mounts where the ujoint goes when you press them out.
replaced my ujoint on the yoke and differential side with their u-joints and the center ujoint was bought from autozone
used a hydraulic press at my dad's work