I didn't know what Prickly Heat was, so I looked it up:
Miliaria - Wikipedia, the free encyclopedia It's often referred to as Heat Rash here. I've had it before, but I just figured I was allergic to the sun - lol!
Wiki says it's caused by blocked sweat glands, so my first and most obvious suggestion would be exfoliation, but that's probably something you've already tried. And I don't think it's ever helped me, now that I recount.
You might also consider where you're moving to - maybe it won't be so bad for you, depending on where you end up.
Burt's Bees makes a sort of baby powder that came up when I searched for 'prickly heat' on their site:
Baby Bee Dusting Powder - Burt's Bees -- I like they're stuff.
Otherwise and to answer your question directly -- I have never seen this brand in the US and I've lived in a few different places. From the website, it looks like they don't even service the US (outside of, like you said, maybe airports). You can order it directly, but it might be expensive so you may want to look into buying a few tubes at a time or to last a year.
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