Broken gear on F355 shock?

The suspension warning on my F355 Spider recently came on. I removed the shock actuators one at a time until I found what was causing the problem. The smalll metal gear on the top of one of the rear shock was broken. I was able to remove the gear from the top of the shock by pushing out the spline. I was hoping that someone on FerrariChat could advise me on how to go about finding a replacement shock gear. Does anyone have an old warn out shock for an F355 that still has a good gear that they are willing to part with? Any other suggestions would be greatly appreciated.