With those as your only comparisons I am pretty sure you will be screwed. Mostly b/c those are all blobby lasts.
Meemin generally makes sleeker lasts. And so sizing the width is more important.
If you are willing to take the plunge (Which may be reckless) you could go an ask meermin for the physical sizing of the lasts and try to size up that way. But you may end up with 1-2 retries you will have to go through.
Do any other fine shoe makers exist in the AU? Get sized by them and then compare your sizing their to that here.
I just realized I totally misread your comment! Many apolgoies. Didn't realize at first read you were talking about Nike and Clark's being the blobby lasts. So sorry for the hasty riposte!