Nerites are NOT mystery/Apples. Totally different species & requirements.
But as far as shipping goes, apples are even easier to ship than nerites. Apples have lungs and can live outside of water. You can ship them well packed in damp paper (so the shells don't get crushed). Have a bit of water in the bottom of the bag to keep everything moist, and fill it well with air. This should be OK for an overnight delivery.
BTW - Mysteries only ship well in warm weather .... they will not survive low temps. <I can't find the source right now, but I remember the lethal temp to be something like 50 or 60F.> I don't know what the temp is in the East, but I think they are having a cold snap ..... So Calif might be OK, but you might be taking a chance to the NE. <And definitely can't ship to Canada ... we are well below freezing.>