I mentioned this in the previous round, but it might be worth repeating here as well just to give an idea using some actual numbers.
My print went from near Seattle, Washington to Oslo, Norway, sent USPS. It was dry mounted on 11x14 board with a custom matte and a backing board. It was boxed at 12" x 16" x 4" and filled with bubble wrap. The total postage cost was USD $22.30. It took eleven days to arrive.
I would think this cost to be near the high end, unless the destination was further from me than Europe. I do think that, in absolute terms, for sending something of that size one-third of the way around the world in under two weeks, it's not an outrageous cost. Factoring in affordability, however, is another story entirely. YMMV...