Personally I would run shielded, 20~24g minimum.
DigiKey is about $1.00/ft for 100ft 4 cond shielded.
Check to see if you have a cable supplier in your area such as Texcan or Anixter.
Prices have soared in the last few years, probabally the price of copper?
Is there a reason they need to be 24ft from the controller? The amp to motor cable is less prone to EMI and can be TEW twisted.