Bottom of window piece
Thank you for reaching out to us. We're happy to look into this. Can you remove an undamaged sample of the piece and show us a clear photo of the end profile? I can't promise we'll have a suitable option but that should help us confirm.
Unfortunately, we could not find the trim piece you show here. Your best bet would be to check with the supplier or manufacturer of the door to see if it is still available. One idea would be to use some window glazing like the 55-204 and a type of adhesive to glue it to the bottom of the door to close up the gap but we can't promise it will work. I am very sorry that we can't offer a suitable replacement option.