It looks like the first four coins might now be all sold out, as none of them appear to be listed anymore.
SEP - Optimus Prime
OCT - Bumblebee
NOV - Megatron
DEC - Grimlock

They have a new one listed though, which must have just been released - Starscream
https://www.nzmint.com/products/tran...oz-silver-coin

People might note that the reverse side doesn't have the Queens head on it, but also doesn't have the King's head either... it just has a coat of arms from the Niue, as that's the island of issue for these coins.

On their Coming Soon page they have Soundwave listed for August 8th, so Starscream probably was released July 8th.
(the first 4 coins were released at the end of the month, while these are at the beginning of the month)

I think the NZ Mint was supposed to be releasing some ROTB movie coins as well, but they aren't on there, so if they did them, they must already be sold out.