Adjustable Window Screen Corner Key

Not sure if you can help with this one or not.If this isn’t something you typically stock, don’t go crazy…
We’ll take anything close we can-jerry rig to make work.
• Screen Corner for a 45° miter
• Roll Formed Frame with Lip
• Spline Opposite Side of Lip• Overall Height:  15/16”
• 3/8 wide
• 5/8 height w/out lip
• 5/16 lip
Cavity 3/8 x 5/16