If it's only going to be a back up blade then I would save your money and the weight by getting a Mora and a SAK with a saw. With these to compliment your main blades, the right knowledge and lots of practice there's nothing you can't tackle, and these won't weigh you down while being very capable and versatile.
Something like the Mora 545 (stainless) or 511 (carbon) weigh next to nothing, have a nearly full tang and are just amazing little knives. There's also the classic #1 if you like wooden handles. These knives will be in the $8-12 range at Ragweedforge or Ben's Backwoods. If you're looking for something more modern and more expensive then check out the 2000 or 2010 (They're "expensive" at around $30 or so) and then there's the new knife line by Mora, but I really don't know anything about them.
My two favorite SAKs are the Farmer (I keep one in each kit as a back up to my main blades, they have an excellent awl that makes a good ferro striker and a great saw, which comes in handy for a myriad of things) and the One Hand Trekker (which has a locking easily opened blade and a good saw, but I don't care for the handle so much).