I've been breeding orchids for 3 generations, and even though I've witnessed successful matings from 8 pairs of orchids, and ended up with over a dozen supposedly fertile ooths, only about 30% of the ooths were actually fertile. Fertility is determined by: after 6 weeks or so, I can see eyeballs inside the ooth if I candle it. And of course, later on, the ooths with eyeballs hatched. The rest of the ooths never had any developing embryos, as if the females were never mated at all. It's sad. That is why I never sold any ooths, and never will, because guaranteeing true fertility is beyond my control and power.
First, 1cm of ooth is awfully small and doesn't sound very fertile. I've had tiny tidbits of ooths (of other species) that hatched 1-2 nymphs, or none at all. And if the breeder is going to cut an ooth...I don't know, that idea makes me cringe. Also, is the ooth captive bred or wild caught? WC ooths are completely a gamble.
Third, as mentioned already, international shipping, especially from Asia, takes a long time. I received some clay handmade crafts from Thailand this year, which took 3-4 weeks. Lastly, you risk getting in trouble, or delays, with customs. One of my packages I received last week was apparently opened somewhere during shipment, but I had nothing to worry about since importing clay ornaments is perfectly legal.