Printrbot Simple Spool Holder
I took Vezkah's Printrbot Simple Metal Spool Holder 2.0 and resized the hole so it fit on the original Simple. Works great on my Printrbot Simple 2014!
The full size is too big to print on the Simple 2014 itself, but I've included a scaled down version that will fit the 2014 - however I'm not sure if all spools will clear the printer on this smaller version - let me know if it works for you!
Be careful with very high prints, I managed to dislodge the string on the Y-axis of my simple because it was rubbing against the spool holder.