<SNIP>A 22 and a thousand rounds is good to have anywhere. But that and something that tends to stop folks sooner, is much more powerful and breaks bone when it hits, is better still.
Even in my scenario, I also would be carrying a more appropriate SD caliber. A few 22LR's to COM would still take a minute to have effect. For 22LR to be truly effective, it needs to be a shot to the eyes, nose, throat, thoracic triangle, or base of skull.
Most folks would not hesitate to carry a snub in 38 for SD, but I'm not sure if they are aware that a 40gr Solid LRN Agulia Interceptor round (this is what I use for non-plinking) from a 10 inch barreled Ruger Charger 10/22 carries as much energy as a range / wadcutter 38 special load or a little less energy than a SD standard pressure 38 special load. Not many of us feel naked carrying a snub in 38 special, though.