It's hard to know. I would assume that they're pretty young, say within the first month and that's why they're so small and skinny. However, I have some hatchlings that don't get into the eating thing very well and now at 2-3 months they're still only 5 or 6 grams, so it could also be an older baby who isn't eating well.
i have to agree they cannot be more then a month old and i cannot imagine the stress the poor things have had to go through in their first month of life with all the handling and shipping so on top of it all they aren't just young but extremely stressed out.