zip ties seems to be a favorite among canoe trippers.most if not all have a SAK type knife with a awl to punch holes and then put the zip tie thru and pull it tight.a photo posted at the bwca site shows a boot with several ties holding the sole back on.
sewing awls are sort of big but a very large needle and heavy thread would work with any sort of pack,tent or clothing.
i have done a few small repairs on things like sleeping bags and canvas packs on trips and i found it's just a matter of taking your time and working slow with what you have...fishing pliers work great for pulling a big curved carpet needle thru canvas.