I am not sure if the seller insured it, but I doubt it. I figure you really take a chance on shipped eggs, it's a gamble in more than one way. I bought 30 cortunix eggs and 15 were smashed, when I informed the seller his response was he would pack them better next time..not as in let me replace those for you. Myself, I would replace eggs that were broken if the extras did not make up for it. But after buying so many eggs online I think I would pack them really well as a seller I've seen how different people pack and I've seen which ones make it to the destination the best. The foam with circles cut is by far the best imo, but the bubble wrap individual eggs works really well too. I think you can honestly tell who cares out their eggs and who does not just by how they are packaged for shipping.
All you have to do is to enter the tracking number in the online USPS tracker and it will tell you if the package was insured. It is very likely that a Priority Mail package was insured for up to $100.
Unfortunately only the shipper can file a claim for damages and the claim has to be filed within 30 days.