Replacing the O ring seal? If you have a friend with a lathe you might be able to bribe him with a six pack to turn down a short length of round stock for you to use as a tool to drive the bushing out. Another way, which I haven’t tried, is to cut some thread into the bushing from the top so a length of threaded rod or a long bolt can be used to pull the bushing out. Myself, I like the first option better
