AFAIK, you by the time you get to them to "check" them, you might as well go ahead and replace all of that. I think my indy-dealer was going to charge $400-500 to do this on my '85 380SE (which I think is basically the same engine, except its smaller)... basically no more than your typical timing belt change on a car with a t-belt. Buy your parts here though to save money. If you are getting the car cheap enough and its a good car, adding more $ to do this for peace of mind would be worth it.