FB have CR buff which means you depend more on CD based db weapon. I not sure swd amp weapon will help you but I guess a good tit DB at least 27% for a start will be good.
your budget is kinda tight right now so the options are limited Let me summarise
1. TIt db 10% crafted CD, 20%CD slotted - ard 180m
2. Tit db 7% crafted CD, 20%CD slotted - ard 80m (guys pls confirm, i not very sure the price)
3. Osm db 20% CD+7 - below 100m, last saw firebonebreaker selling. Think ard 90m
OSM DB 27%CD and above are out of your budget as the price is ard 180m and above.
For ORB/Crystal, i not very sure.