No its not a plug retainer Jim, its a whole pin stack, Im guessing this lock was part of a system at some stage. I found an Ilco to factory cross reference here
http://bgdistribution.ca/wp-content/uploads/2013/10/ILCO_CROSS_REFERENCE.pdf, which seems to suggest that the part number should be Z1-62A2-6 if crossing from the 1001A2. Im guessing the 6 on the end denotes the pins, so I switched it out and did a Google for Z1-62A2-7, but to no luck.
Anyway, have shot an email to the key detective at BlueDog, refered them to this thread, so hopefully they can come up with something for me and ship it downunder. I think this is the part that you pay the premium for with them

I also like to buy a handful of blanks to keep in the shop when I come across something thats rare / hard to source, just keeps me happy in the knowledge that I have another, and I have a reference to the part number so I dont have to go through this process all over again everytime.
Thanks again for your help guys, with something like this the local knowledge really helps with part numbers and such. Were pretty much 90% Lockwood down here in OZ, so hopefully I can return the favor in the future.