Help: Fix Closet panel (broken mirror)

Hi,
I am helping someone. They have a 15 ish year old house. They have a sliding closet panel (mirror). One of the mirrors broke. I can't seem to find a replacement that guruantee's that it will go back in the track.

- HomeDepot etc charges a lot to make the custom size door but they don't know if it will go in (and how).
- A kijiji company quoted me $60 to make the door, but they take not responsibility if it will fit. They only work with opening size (not panel size). I offered to take the old door to them , they say its irrelevant :S

To take it out - a contractor just yanked it out. I have contacted windows / doors people - they dont do it.

The frame itself is fine - I just need that fixed with any material (doesn't have to be mirror) and put back in.

The top part seems to be like this: https://www.wayfair.ca/PrimeLine--Close ... 24EALw_wcB

Bottom part is just plastic tab that goes in the track.

What is the most inexpensive way to get this done?