Is there not more than one Music store around? I buy mine from Tom Lee and they are top quality. You must have meant 6 feet not 6 inch... that would not reach anything : ) A 10' cable is $22 Can, And they often have sales where I'll pick cables up half price.
I would think Sweetwaters cheaper cables are fine too. Not sure about MF, I seem to remember the cheap stuff being,,, cheap stuff...
http://tomleemusic.ca/19651 Oh and a small point,,, They are not technically speaker cables, They are balanced connection or patch cables.
A true Speaker cables as you probably already know is unshielded wire and can have different connections like binding post, Banana, 1/4" TS or Speakon.
A balanced cable has many uses beyond patching in a powered speaker. You probably knew this but you title threw me off for a second.