Covid really did fuck up the gun and ammo situation. A shotgun is ideal, but a handgun can definitely do the trick. A 38 or 45 would be best I would think, but even those are hard to find with covid sometimes depending on where you are. The main goal is to sever the brain stem, so a lower caliber handgun might have trouble getting through everything it needs to get through to do that. From what I read about handguns, in the mouth or above the right ear is how most do it. Wishing you good luck and peace if you choose to go this way. I am also going by firearm.