I'd just get something in the "decent" range - I wouldn't spring for the $50-$100+ cables for those monitors. Those are "entry level studio monitors", right? So that's the type of cable you need. And I'm not saying that to be disparaging so I hope you don't take offense! It's just that monitors range from $100 per pair to $30000 per pair...
I'm afraid I don't know how to make sure of that because I'm not an expert in that area. Do you see an appropriate product here: http://www.thomann.de/gb/cordial.html