RE: Replacement Gears
There used to be an ONLINE racing series where you downloaded your track times into a data base and they compiled the data and built graphic display so you could play the race back on your computer. It was great fun. The trick was to turn consistent track times.
I had a 4 lane 1/24 scale wooden track in my basement for awhile where I drove all the old 1/24 scale COX classics. I still have the cars.