Thanks for all the great information. There is a chain of "U pull it" yards near me. They work off a printed price list so you know the cost beforehand. Seats cost $20 each- no track.Tracks are an extra $20. So for $40 I can get the whole thing. The downside is they do not keep track of inventory; you must go in person and pay the $1 admission to see if they have what you want.
When I'm ready, I just keep going until I find what I want.