Stephen, thanks for posting the Bell, Book and Candle phones. I've seen that movie many times and I had always thought Kim Novak's phone was dark gray, but I didn't have a factory DVD to tell the color for sure. The cords looked to be the same color as the phone, but it does look moss green in your shot. That movie is a little grainy and it's hard to tell, and dark gray can look green sometimes, and vice versa. I hadn't seen the brown phone on the secretary's desk, so thanks for pointing that out. I agree that the one in Merle Kittredge's apartment is dark beige.
That's a very kooky movie and Kim Novak is very beautiful and beguiling. It's the second movie Jimmy Stewart and Kim Novak made together in 1958, the other one being Hitchcock's Vertigo, and the last movie Jimmy Stewart played the romantic male lead (he turned 50 while making the movie).
What I use for screen caps is Gadwin Print Screen. Someone on the group recommended it just after I started posting. Works just fine, but I have to turn off the Hardware Acceleration in my display.