Just a precaution.
So politics, racism and all the other fodder aside, a lightweight magazine carrier all I'm looking for. I will likely only wear it during tactical training drills. Thanks to those who managed to address the actual request. The rest of you should go drink a beer and watch TV. Relax a bit.
Being prepared is good. However when you ask a question in the way you did, it really sounds like you don't have much quality tactical training as the question is so broad as to be meaningless, and someone with training would already have an idea of what they want. Your question sounds like 'if my house catches on fire, what kind of fire extinguisher do I need?'
You also mentioned it was to protect your family, which leads one to believe protecting family is the real goal. In a SHTF situation, the best way to protect your family is to go to ground, rarely is there no option but to fight. However, admitting this really screws with our wet dreams of being the hero.
But, seeing as you only have an interest in toys, and consider advice on strategy and tactics to keep your family safe unwanted, here are some questions to help. Are you looking for a "pack" to carry mags, a chest rig, a drop leg set up, belt holster? Or, are you hoping someone will point you towards one of the options as you don't know? If the latter, go chest rig, it works well while also being tacticool. Do you just want one spare mag on hand, or do you want a full combat load out? Do you need to work as human cover for your children, or can they manage themselves? Will you have support (i.e. armed family members) or be solo? Will you be trying to make a fighting exit or hold ground? All this would effect my recommendation on how to carry extra magazines and what to get. But if all you want is a suggestion, get a Blue Force Gear Ten-Speed.
As for other tactical gear, get a two point sling, a weapon light, hand held light, and an LPVO. Get a secondary. Add some large zip ties or flex cuffs and partial role of duct tape squished flat. Get a suppressor. Tape green and red chem lights together. Add a torniquete, two chest seals, hemostatic gauze, 11 blade scalpel, bougie, 6.0 ETT, and a decompression needle (or hemostats). I'm assuming you have ruled out trauma plates, a ballisic helmet, and NODs. If not solo, add communications gear.
At this point you should consider something other than the Ten-Speed or pair it with a small pack. Perhaps something by 5.11.
Note, you also asked what I would want, not much of this would be on my list due to the strategy I would choose. But, I have no beer or TV, so I had to opt for dandelion wine and a text book instead.
Go with God and may you and yours stay safe.