Cotton and Vaseline works great, cheap, make all you need for pennies and stores forever. That's all I use in my various kits anymore. Try it, if you think you need more there are other options.

You can also make firestarters with paraffin wax melted into just about anything flamable and absorbant. I use these made from egg carton paper, and wood shavings for firestarting in the rainy season. Mac