Associated still supplies parts for cars that they've had out for over ten years. Also some of the easiest cars I've worked on have been associated cars. I can change just about any part on a TC3/4 in a few minutes. Parts are cheap, but the car is tough enough that you won't have to use them right away.
I would also put in my vote for the TA05. It's a belt driven car. Great for someone who wants to get into the hobby at a good price. The car also has loads of upgrade options. So the prefomance of the car can keep up with the skill of the driver.