For the individual car I would recommend the IMEX 1:43rd scale display case. They seem to be of good quality, they are stackable, and come two to a box for somewhere around 5 to 6 bucks.
Sometimes the rubber tires will react with plastic bases. So to prevent this or to enhance the appearance of the display case, I use self-adhesive felt in either black or green to set the car on.
Hope this helps.