Rios blister virus was treated with ear infection solution for dogs -worked like a charm and I believe its oil based but was really thin and cleaned up easily- believe it was called otimax? cant recall for sure tho.
A good antimicrobial cream is Silvadene cream (silver sulfadiazine 1%). I use it for minor skin wounds to aid in healing and help keep infection from forming. I'm not sure of the shelf life, but you can get a small container of it from your vet's office to have on hand when needed.