All european gun maker have 9,3x62 or 9,3x74R in theyr catalogue.
But only voere still produces 9,3x64.
And of course a lot of gun craftmens .
9,3x66 is a strange thing.. It was intended, maybe, to fill the gap between x64 and x62.. But it's only chambered in sako and tikka rifle, only in short barrels, Max 56 cm...

Way the hell?