those, there are about 80 million handguns in circulation. And of that 80 million, I would venture an educated guess that there are less than 50 million holsters, to match. This is because most handgun owners are not regular handgun carriers . The most lopsided "gun-to-holster" ratios are with .22 rimfire handguns, and large-frame, long-barreled revolvers. I suspect that perhaps only 25% of those handguns have an accompanying holster. There are also more rifles and far more shotguns out there than there are carrying slings for them. (I'd roughly estimate that less than 10% of shotguns have slings.) These disparities represent a huge opportunity for a post-collapse cottage industry. In a post-collapse world, suddenly almost everyone will want to be armed at all times, and they will be eager to barter to fill those needs. Also keep in mind that because of its length and padding, the venerable U.S. military M60 sling is one of the most versatile slings for re-purposing. They can be used with a huge variety of rifles and shotguns. So if you don't have craft skills, then you can at least buy a pile of those slings to keep on hand for barter. (They are quickly and easily shortened, with a snip of scissors.) I should also mention that nearly any handgun with a positive external safety lever can be safely carried in a Nalgene water bottle pouch. ( Warning: Glocks and other "safety in the trigger"-type pistols can only be carried safely in specifically-made holsters