What steering coupler do I need?

I was able to cancel the order, thankfully.

Mine isn’t missing. I’d be lying if I said I knew what I was talking about when it comes to this, so I’m honestly just going on what I am told. I’ve done a lot of looking on the good ol’ interweb and haven’t found many answers. My buddy is the one that said to change it over. Regardless, I either need to find a direct replacement or a “rebuild” kit. If anyone knows anything and wouldn’t mind assisting with that info, that would be awesome!