Attached Link: http://www.planit3d.com/index.htm

There are tons of car models out there that can be imported into poser. if you find the model and it's free, email the author and see if you can use it commercially for the wall, most will be happy to let you, some won't but it's worth the time. Planit3D has a bunch of cars that could be textured with the right look from the movie. check out the cars and play with them. it's a start anyway.