Yea... if just the ball is worn out you are in good shape and just get the rebuild kit off the shelf.
If your shaft that the centering ball rides on is wasted... you need to take it to a driveline shop.. it's welded to the shaft and needs to be cut off, new one installed, all new U-joints and rebalanced. Shouldn't be more than $200 for that.
IF you take it apart... DONT LOOSE THE SPRING in the centering ball ( could stay in the shaft though ) and make sure all the needles are seated properly in the ball prior to reassembly.
Pic for illustration purposes