The need to have a RUT ( ID card number ) seems to be a requirement for any and all online transactions in
Chile, from bus tickets onwards.
Can't help with international
shipping but I think the postage would be horrific. ( Domestic postage 3 years ago was Ch$15,000)
Simplest option I can suggest is just waiting until you arrive in
Chile and then getting a local friend to order it for you.
I bought mine over the counter from the chart agents in Montt and you could get them in the Post Office in Pto Williams but that was quite a few years ago.
Sorry I can't be of further assistance.
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