While timing chains can fail, it isn’t common. Many (but not all) do get loose enough before finally breaking that they rattle around inside the motor and make some noise. Don’t worry about the timing chain, just drive on.
My cousin is a professor at a university in LA (state, not city). Until just last year he was still driving (get this) an old Geo Tracker. And the years he spent there from student to professor definitely showed in the vehicle.
Most of the students I know tend not to care all that much about the cars Dad & Mom paid for - especially if they’re used. They get abused, parked on the street, “bumped” into in every parking lot, used as ashtrays (whether he smokes or not), beer holders for the party in the woods, and every other thing you’ve done in your life and more. If you’re in the city, any kind of SUV is big, and if you’re not, it’s a big thing to cart friends around.
Keep the '97. Fix it up, do the maintenance it needs, and let him beat it up for a couple years and not feel too bad about it. When it gets to the “Dad, it may not make it home this year” stage, THEN replace it with another used vehicle for him.
You’ll be glad you did.
Chase
An older car is immune to being abused the same way a new car is, in a school parking lot. If you are content with son’s ability to handle it and it is in good enough repair. Go for it. It won’t be worth any less later than it is now and you might as well keep using it till it needs major work. Minor repairs are a really good investment for now compared to the expense of buying new.