The equation for up to steel arrows is this: [(price of bar)/15 + (price of feather)] x (.85 to 1.15)
So Bronze Arrows are roughly 14 to 25 gp each.
Iron Arrows: 18 to 30 gp each.
Steel Arrows: 30 to 55 gp each.
Now mith arrows in bulk is hard to gather, and mith bars are somewhat expensive. 80 to 115 gp each.
Noone can make rune arrows from scratch, neither that many people can make adamantite arrows from scratch. Addy arrows 115 to 140 gp each.
Rune Arrows, 170 to 200 gp each.