Do it...make a kit!

Half the fun is actually building your own (also cheaper than purchasing top of the line pre-assembled kits), plus you can "test" your gear in a controlled enveirnment to make certain it performs as claimed in case you "really" have to rely on it. -10 and a 35 MPH wind is not the best time to find out that sealed container of lifeboat matches has deteriorated over time and become totally useless for lighting a fire!

I currently have three PSK's.
The smallest is contained in an Otterbox brand small clear watertight case and while minimal, it holds more items than an Altoids type tin. Throw it in a cargo pocket or rain jacket and at least you will ALWAYS have the basics with you.

Next in size, I use a Blackhawk E&E bag (found it new for 8 bucks) that has a very generous belt loop/velcro backing. It holds all the essentials minus food/H20.

Lastly is my trunk kit that is basically a black expandalbe duffel that doesn't scream "tactical" or "survivalist nut case." In that I have enough food/H20/first aid supplies and survival essentials to make a tough situation not so tough.