Hi Ed,
Not sure if this is what you are looking for, but you can set the end marker in the transport bar. See the attached screenshot.The number underneath the tempo is the end marker. In this screenshot it is set to 130, but can be freely set to any bar number.
You can also achieve the same result by dragging the end marker in the bar ruler. This will be at the very end of the timeline and looks like a small opaque colored box. Click and drag it either left or right to place it either earlier or later. The changes will be reflected in the transport bar.