Mystery sliding door track

The door track that our sliding glass patio door slides on broke this weekend. I had never paid much attention to it but when it broke I was surprised when I realized the track was a plastic resin and not aluminum.

The rubber weather stripping had been peeling away for a while but we have not had any flooding issues as this door leads to an elevated rooftop deck with good drainage.

I want to replace the track but I am in need of some help to identify what exactly is currently in place - help!

- yellow circle on image: shows where the grey plastic door track broke.

- red circle on image: shows what the strip of rubber weather protection looked like before the rest of it peeled off.