Wired doorbell need terminal wire screw size/replacement

I am attempting to install one of the wired ring doorbells. I unscrewed the wire terminal screw too far, it popped out and dropped and is lost outside. Where can I get a replacement? It looks like the wired kit shown [here](https://support.ring.com/hc/en-us/articles/115005688763-Spare-Parts-Information), bottom of page, has the security and mounting screws, but not the wire terminal screws. Is the picture incorrect? The kit looks like it has everything except what I need. thanks for any help.