You're about done for uniques in Normal, start looking for dual affix greens from vendors. And, of course, you can farm Soronis in Act IV for Bramblewoods.

Remember that you're not doing much physical at all so finding a higher level unique isn't going to help. They mostly just buff up the bow's base physical damage and/or give more +% damage because that's what conventional archers need. What you want is to stack as much flat Lightning and +% Lightning as possible, along with +% attack speed and +% piercing for the Scatter fragments.

Have you kept some Zeus relics from Act I?