[CR1] Water Arrowhead = Water Arrowheads do not exist in game - Bottle of Water + Arrowhead [CR2] Fire Arrowhead = Arrowhead + Cloth Scraps or maybe campfire/forge? [CR3] Smokescreen Arrowhead = Fire Arrowhead + Oil Barrel (Wont be able to use cup of water or will conflict with explosive) [CR2] Freezing Arrowhead = Water Arrowhead + Essence of Air (too expensive?) Freezing is quite powerful so I don't think this is to expensive.
CR level to keep in line with other recipes while trying to maintain some balance.