[Phil Kalbfell]

Brian is right, no need for updated hardware IF the old stuff is working OK.
4 of our tracks still run on old XP machines. 3 are still using serial Trackmate boards brought about 20 years ago.Sensors and IR transmitters brought for a few dollars.
Other rally track still using Printer port.
It just depends on how much you want to spend.
The Trakmate or Viasue  hardware works great IF you want ready to use set up, but it does come at a cost.
I would download RC have a play with it, look at the wiring info included.
It may save you a lot of time and effort.