these can be purchased for 1600 a stack in Bastok/Sandy when they are in first place. these are the arrow of choice for 24-40 if you are soloing worms due to the high base damage. you won't be needing the +5 racc from horn arrows if you're soloing since you'll mostly be going after EM / T mobs. during those levels you should have something like +20 racc just from 2x archer's knives.
