I would say a complete multivitamin (like Millennium Gold or Dumor Vitamin God or Vitaplus - you only need 2 ounces a day!!) and hay is all you need. They should be fine in the minimal work they're doing. You can stretch your budget a lot longer on that and not get the crazy hotness that comes with many commercial feeds with extra sugar or grain. If they need more food, more hay is best.