There is no register for the general public to check on part availability, this is in-house with CJD. But ALL manufacturers by law MUST keep a strong inventory of ALL spare parts for their products. The worse case scenario is they have to order the part in from another state, ie Melbourne but certainly NOT Germany, this is BS.
Baxter, they're unfairly giving you the run-a-round you've been far too passive for far too long, time has long past where you need to be assertive!
If this was happening to me this is what I would have done 6 weeks ago:
1. Go to LM Holland Park (I think that's where you mentioned you purchased it) and start thump your fist on a desk demanding IMMEDIATE action.
2. If that does not work, call Jeep Aust from the dealership floor and demand IMMEDIATE action.
both 1 & 2 work best if there are customers on the floor. This worked for me when I was in my 20's after buying a 2nd hand car that blew a head gasket within a week of buying it. The closer the customers got the louder my voice, it worked a treat and I got that dealer to put in writing that he'd repair it.
3. Fair Trading is an option but takes time.
4. Last Resort - Go to sign writer and get him to measure the Jeep and print off some very large lettering that says something to the effects THIS JEEP IS A DUD on all 4 sides and park it in a prominent position outside the dealership. If you warn the dealer principle of your intentions you'll have his undivided attention. Don't speak to the idiots under him, they don't care.
Whatever you decide to do, the long and short of it is YOU NEED TO ACT NOW, DON'T WAIT AND RISK DAMAGING YOUR ENGINE.
Call to see if they're open on the holiday today.