Preeeeetty much everything this guy here has (I can dream, can't I?), plus a Swamp Rat Rodent Waki, a crapload of ammo for that .357,
Boy this was pretty fun

I hope to God something like this doesn't happen though, because I don't own anything of what I just listed, lol
Umm, a 357 revolver's cylinder is actually shorter than that. (Unless the pic is foreshortened or elongated or something like that.)
My knife choice would be a 3-4 inch, high carbon fixed blade with a belly. (Fallkniven F1 comes to mind.) 2 of them. That's it.
Guns? For Zombies? 223/5.56 frangible ammo ONLY feeding a bullpup. (Steyr-Aug comes to mind. ACOG sights.)
Handguns? None. I WILL NOT gonna do no house/building clearance in the middle of a zombie epidemic you betcha! Keep SOME distance (many yards! yikes!) to clear a path is the only way to go. Nobody but NOBODY has dealt with splashing bodily fluids on yourself and potential consequences in zombie movies and I for one am not gonna be the guinea pig. Kukri/Katana wielders BEWARE!

Several BIC lighters. Tinder.
Several bombproof flashlights. No batteries, s'only for 3 days. (HDS/Ra lights come to mind.)
Water filters, purifier tablets, 2 1.5 liter Nalgenes (not just for drinking), and Mainstay Energy Bars for 3 days for me only. (Damnfools will weed themselves the first day out.)
Bottle of alcohol. (Bushmill's comes to mind.)
Clothing on my back, boots on my feet, hat on head and gloves for my main tools; my hands. Zipties, bandannas, shemaghs, industrial strength trashbags, 550 paracord, couple shirts, underwear, socks, radio and 2 pairs of my prescription glasses.
FAK.
Kifaru pack to hold it all. (X-Ray comes to mind.)
This is for three days only. If you don't make it in that time, you're better off dead. Save that last bullet. Trust me.
Edit: Almost forgot! Binocular/monocular. Gotta see where your best path lies.