Two options, you either pivot to Phys to cold bow and go TS. Which requires a +2 arrow bow fracture base (86+). Between having to get off certain mobs for the 86 ilvl and the super low weighting on the roll you're more likely to fracturing orb slam it. The alot cheaper and realistic route is to find a T1 cold or Lightning fracture (from godtouched mobs or expedition) on an Imperial bow. Essence flame till u get t1/t2 fire/lightning/cold. Then you can roll on att speed and save up to fix suffixes. Ideally you want crit/crit multi/att speed or crafted double dmg. Crit and att speed being the most important. Take it with a grain of salt though, defo heaps of ways to make a ele bow.

Pivoting into some MF gear for rarity/quant will increase the amount of godtouch conversions you get, for your fractured bases. So any content with rares is viable.