Pylon hydraulic leaks are a known A320 family problem of late and Airbus have a special check to inspect the pipes and fixing bushes.
Given that a lot of pipes are being changed its not surprising to hear they needed to be sourced from Hamburg.
Depending which of the pipes has gone it can be several hours work to replace them, what tends to happen is the teflon bush between the pipe and clamp frets until it's gone and the clamp block rubs through the wall of the pipe.
We've had a few leaks before Airbus came up with the check and found a few in service that would have leaked if left to deteriorate.
As for finding the reg, no idea. Put a post with the details in the spotters forum below and I'm sure someone will track it down.
SIL 29-100 refers if you have access to Airbus docs.
Last edited by Fargoo; 1st Jan 2013 at 16:20.