Panacur won't do anything for the tapeworms.

Why don't you want to get the meds from your vet? They aren't expensive whatsoever(maybe the Drontal Plus-praziquantel).

You're going to need to weigh the snakes on a gram scale and get exact weights, calculate their dosages, crush pills up, mix with water, and use a red rubber feeding tube(from the vet) and a 3ml+ syringe, to get it down.

If you had 20 snakes, I might understand where you're coming from financially, but if you have less than 5, I would say just support your vet's business and get the meds from him.