Need replacement mirrored closet door track

Probably purchased these doors from Home Depot and manufacturer is likely "Contractor Warehouse". I replaced the original track in one of my other rooms years ago with a heavier duty aluminum one that will not rust. But having trouble finding one to work with a nearly 8 foot opening. I hope you can help. Also, can I use one that is concave in the center, but with the same dimensions and wheel channels? The one I have is up in the center and is secured over a wood trim piece. The one I have is white (preferred) but grey will work.

Thank you Tom. That explains why I haven't been able to locate a replacement track. I'm not sure how I will proceed at this point. I may be able to get by with the existing rusted track now that I have painted it and the rusted bottom frame of the doors, until I can afford to replace the doors. Unfortunately, comparable doors right now are nearly $1000, so I may switch to something else entirely.