Right now I examine some SSRs, and most of the samples I have are equipped with these metal "pads", with screws with square washers to squeeze the cable. I know it sounds silly to ask their name, but if they do have a name & are commercially available products it would be appreciated, because then I will be able to prepare a prototype of a product without having to manufacture these parts.
The SSR's in your question are called screw terminal SSR's
the terminals are also a type of screw terminal connector. Those are very hard to find mostly those are custom made according to their mechanical and electrical design (sheet metal work).
Usually Screw terminal type SSR's to be connected to wire using Lug terminal.