I need to replace several ugly metal window screens, but these screens don't have vinyl or rubber spline. To remove the old screens I had to pry out a U-shaped peice of aluminum that fits into the spline groove. Even prying carefully, there's no way to re-use this "spline". I have some larger-than-normal diameter vinyl spline, but it doesn't begin to hold the screen. Is there some type of replacement spline I can use--either vinyl or aluminum?