it should exist but it is NOT on any of the Feather Merchants.. i used to love this Staff on my old friar. iirc at the time it was the slowest , most hard hitting staff in the game (sucked v pbt and shield classes though haha)
i asked this in /advice a cple days ago and nobody knew the answer
Make a ticket in the tracker ( https://tracker.playphoenix.online/issues ) after you search and make sure there isn't already a ticket for it. I expect it may into the category of items added slightly later, or simply lack the evidence, but good luck!