Errol,
Glad that you've ordered the Altoids from the US. You know, a few days ago, I saw a link here for an Aussie distributor in Melbourne mainly, but with many other locations in AU where you could get the Altoids smalls.
However, for the life of me, I've checked every question in this forum and cannot find the original question/answer where it was posted. PM must've done a purge on some of the questions. I've even looked again and still can't find it. Uggghhhh!
Anyway, you mention that they are a slightly different shape. No need to worry. You just need this general size and shape.
Good for you!