Gentlemen thank you for your replies.
Based purely on genuine examples of WW1 NZ sandcast badges that I have handled, and all of which had some sort of an aged patina, I am leaning towards this badge being a copy.
As mentioned, it is unlikely this badge would have been worn in the Middle East, however it is possible that members of the Otago Mounted Rifles who had served with the NZ Pioneer Battalion may have had copies made.
Having done a little research on the Rarotongan company in the Middle East I have as yet found no evidence of them wearing any badges except for the NZNC oval badges.
The following link shows several photos of Rarotongans, the following photos are of what I believe to be a genuine sandcast NZNC badge are copied from post #52 of that thread.
https://www.britishbadgeforum.com/fo...ad.php?t=22199
