Pox Vaccine needed for day old chicks

[Ladyjustice78]

So, I have older chicks that have fowl pox. I'm trying to just keep them cool & hydrated & treat symptoms. My older flock in the coop are fine. These are in a grow out tank & have the sores, etc. I have some chicks set to hatch next week. I have the poxine vaccine coming in and am going to vaccinate some pullets in my big coop that have zero symptoms. Looks like I can't use that vaccine for the chicks set to hatch next week. Reading, it looks like I need something called Poulvac Chick-N-Pox M. Vaccine. I can't fine it anywhere. Does anyone know where to get that? One person said I could use the poxine vaccine and just use one needle instead of the double needle applicator in the wing web. Anyone know?