Light Stand adapter with 1/4 x 20 Thread
Two tripods to support a long camera slider is a good idea, but if all you need is just a little extra support you can get away with a simple Light Stand. One solid tripod in the center, and a Light Stand at the end should do fine. The Konova Camera Slider offered light stand adapters as an optional piece of equipment, so that you can use inexpensive Light Stands for additional support or to get some different slider configurations. I believe they sold for about $18+ shipping. You can actually find them for less than $10 bucks via B&H Photo. (above)
Two light stands with adapters for sideways sliding
One thing that Konova does throw a deal on is collapsible Light Stands. This is one thing that I really hate about traveling even with light weight stands. They are just a bit too long to fit into your average bag. I carry three small stands with my 3pc. 500 LED kit and am forced to use a really long bag just to pack it all in. The Konova folding stands shave down quite a few inches from it's minimum folded length. There are other versions of these which they will call 'Reverse Stands' and you can find some here: Reverse Light Stands
If you feel my pain, these types of folding light stands do exist for a bit cheaper and they make packing things up (with your slider) a whole lot easier. Found below: