If you don't have replacement milk, you can use canned goat's milk. You can get it at the grocery store in the canned milk aisle. You want to use this more than pedialyte or gatorade, although they will help.
You can give it to them with an eye dropper but a bottle would be better. Most walmart stores sell the kind of supplies that you need and some are open 24 hours.
Try the goat's milk (canned) and this should help. But encourage them to nurse as well. The more they nurse, the more milk mom will have.
Let me know if you still have questions.