Storm door retainer strip
Hey there. I am afraid we don't sell this exact retainer strip. These are very difficult to supply, since every storm door manufacturer changes their design for these fairly often.
Instead, what we do is use retainer clips instead of the full strip. See our 70-180 clip and 70-112 thumb screw for an idea of what I mean. Distributing these clips evenly around the door provides the same level of support as the retainer strip but without needing to be an identical match. This is how they did it back in the day and we find that it works perfectly even on newer model doors.
Alternatively, if you have enough of your old retainer strip you could cut it into equal pieces and place them evenly around the window. This would work just as well as having entire strips.