After further investigations and data collecting, we can say that the trade prices and currents aren’t predictable for now, the movement of the prices and vendors changes hourly, depending on the server you are on. Meaning no trade guide or sheet is currently accurate, the best way is to just look around when in outpost to sell your commodities
In that matter, if you need silver, I can only advise you to sell golden rhum and gin to scurlock, and golden snuff and opium to rahma.