The last time I had a zipper break on a favourite jacket, I thought I would need to find a complete replacement and have it sown in. At the sewing store they told me about the "Zipper Lady" who has all the little bits to repair zippers. I used her first last year.
The tab broke off my favourite riding jacket yesterday, and I got it fixed while I waited this afternoon.
Before.

After.

How to contact the Zipper Lady.

Peace and grease, Dennis.