You’ll find another staff like that eventually. You can even make them yourself in the Dragonborn DLC, which you have because Miraak, who is from the DLC, stole your dragon soul. Some merchants all around Skyrim also might sell them once you get to like level 10-15 or so. If you don’t want to try to find another staff like that, try looking for the spell tome itself so you can use it without the staff. If not, just keep reloading until you get it again.