Since it's only about .05" wider than normal track, I'm not sure of the tolerances on track are that tight that one could not just put the car on normal track. An older piece of track with wooden ties would probably work best. I'd avoid FastTack or Realtrax. If you chose tubular track, you could probably bend the tabs on the ties to separate the rails by that amount.
I measured the distance between rails on a piece of 2 rail flexible track and it came to a bit over 31mm. With a little bending I would think you could get to 33mm.
Since you only need it for for display, you could take a piece of flexible track, cut the clips that hold the rear rail near where the trucks are and bend the rails out enough to get the 33 mm you need.