Well, these are gone already (phew!
) but yes they would have been 7 or 8 days old when you would have gotten them, but that would have been only the oldest ones (obviously), and I have read that quail eggs do better if they are 5 or more days old when they are set. I have always gotten good hatches on quail, whether they were shipped or not. The only 'bad' hatches I have gotten were when I first started hatching quail, but I've gotten much better at it!
But I would say for sure that it is safer to ship buttons at least 4 weeks of age. They are almost fully feathered by then, and they are still small (when are they NOT?) so the shipping wouldn't be all that much different I'm sure! Whatever type of fruit you would put in the box with them would probably weigh as much if not more than the buttons would! I've just read on here too many times about quail chicks dying in shipment, or shortly after they arrive, they are just too fragile to ship that young.
I should have more button eggs by the end of next week if you're interested. I have one hen that is acting like she wants to go broody, so I might just let her and see how she does. But that would still be 4 females that should be laying, so only a few days to get a dozen or so.
I've sent eggs to Chickiechick before that were at a week old when they left here, and she still had 14 of 19 hatch.
ETA: And I sent some to gabrielle1976, 17 eggs I believe. Considering I only have 5 girls (then I think there were 6), it would have taken 4 or 5 days to get that many, and I believe it was longer than that, seems like I was only getting 2-3 eggs a day then. She had 15 of the 17 eggs hatch, and now she's griping about having too many!