Aloha!
I have proposed redoing the screens on the house I rent for the landlord. All the screens are wood framed and moulded. Fifteen of them --- all the ones for the double hung windows --- secure to the exterior of the window frame by way of spring loaded plunger pins on either side of the screen. The bulk of the pin is embedded within the screen frame with the securement end plunging into the window sill frame and the other end protruding out for pulling by hand/fingers to remove the securement end from the window sill frame.
I've searched multiple websites for a similar looking plunger, but have yet to find any that appear to stock anything I can readily order on my own.
I've attached several photos of the pin --- installed and removed --- to aid your identification process. I regret I'm unable to provide any model or part numbers or other helpful information.
