Replacement spline

I'm searching for a replacement for screen splines off my patio, it's an aluminum frame, like a pool enclosure (see pics) the spline is flat, Tshapes, with a bulb at the bottom of the T. A round spline if .165 fit very tightly, but did not completely full the channel with the screen under it. I think this patio was built around 1993? The house was built in 1951. Any help is most appreciated. Thank you 
Marc