please help Packing Methods for shipping

these creatures have not eaten for 3 days before the trip also they will be in shipment for 9 days so im not sure if they will live or not i put them in kordon breather bags with foaming and rapped the box tight

Anyone know where to to get heat packs? I've seen them on aquabid and amazon, but where do they get them? I'd like to buy in bulk to get a lower price.