Hmm. Once I start shipping it anywhere it's much the same to me, if you're prepared to take on the risk. You could be right about the slotted holders, I have no way to verify at the moment (sadly!). I have opened this in a changing bag in the past, verified it was plates in there and taped it up, that's all. (and it was about 15 years ago so I don't really remember!) I think they Xray international parcels pretty hard these days but they may survive (your call whether you want me to put "PHOTOGRAPHIC MATERIALS DO NOT XRAY" all over it or not - it might help, or it might invite 'em to zap it extra hard - you never know and with this you really won't, as it might already be badly fogged or it might be relatively OK).
OK then. I will pack it up and see how big/heavy it turns out and you can change your mind when we both get sticker shock at the cost.
Best
Lester