Are you asking about the window scraper , between the outer door, and glass ?
If so, the glass must be removed to replace it......and I have never found a source other than luck at the bone yards.
Now masking under it to the glass..... and cleaning very well, I've found coating it with windshield urethane. Smooth with razer blade. Keep it thin, but push into the cracks.
Let dry. It works very well actually.
Hope this is some help.