Bottom track for sliding mirror closet doors

We want to replace the bottom tracks on the sliding mirror doors at two closets. We need a 48 inch and a 72 inch piece. The doors were installed in 1990. It appears your product codes 23-242 and 23-240 are similar. I need to confirm that the bottom rollers are convex. I believe they are. There are no markings, names or numbers on the tracks.

The rollers are convex.