Most vets will call in/mail in prescriptions to your choice of online pet pharmacy. If it's not expired, they should not want it to, nor need to see/test the dog to get it. They like to, but if he's been on it, with all that's going on, they will, hopefully, not let it lapse.
They might even charge something for doing it, but being able to get it on time, especially with your weather, would probably be worth it.
Please let us know what they say. (You may want to look online before calling to see which online pet pharmacy has the best price...including shipping, in case they agree. The pharmacy might even call them, it would depend on who it is.)
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