Casement, bottom track
We should be able to help, but I'm not sure exactly what it is you need. Can you remove the track from the window and show me a clearer photo of it?
Could it be you need the hinge? If so, consider our 36-048. This should work for you as long as you replace the top and bottom hinge at the same time.
If you don't need a hinge, then we'll definitely need to see whatever it is off the window.
The size of the black slider doesn't really matter if you're replacing the entire kit. As long as the base track is the same length as ours at 10", and as long as you replace the top and bottom hinge assembly at the same time, then our 36-048 should work perfectly well as a replacement for your hinge.