Here is a reply I recently posted for a similar question. Maybe contact Johnsonite to see if they make anything wider to fit into track base.
Install track base. Look at the MT-00-B track base on this web site:
It has a flange on one side that gets nailed to the floor under the carpet. That flange has pins on it to grip the carpet.
The other side of the track base butts up against the edge of the tiling.
That side has a groove in it so that you can press in a "T Molding" like these:
There are different kinds of T Moldings for different heights of flooring on each side of the track base. And, those T Moldings come in 48 different colours, but most places will only stock brown and black in each kind.