Clip to hold screen in
Thanks for reaching out to us. I've never seen this screen clip either, but that's honestly pretty typical. Most window manufacturers produce one clip for a window Series before replacing it entirely with something else. There's about a billion different styles that all do the same job, and they change from year to year and window to window.
The good news is I think you can use our 70-176 slip-on clip as an alternative. This is a very simple clip that clips over the screen frame and braces it against the window frame. There isn't really any such thing as "universal" in this industry, but I personally consider our 70-176 as close to that concept as you can hope to find. I've successfully used it on a ton of different screens. Look it over and see what you think.
You're welcome!
Best of luck on the project and please feel free to reach out if you had any other questions.