:Where can one find these medications listed below?
Betadine is available at any drug store. You need the antiseptic solution, not the cleanser which also contains soap. Silvadene will have to be acquired through your vet. Betadine ointment or even Polysporin from any drug store can be used until then. It sounds like the situation may be beyond responding to topical treatment alone and likely requires systemic antibiotics if there is to be any hope. Good luck.