Timing chain cover gasket leaking

[Lawrence collins]

My 2011 XF is leaking Oil on the bottom of the timing chain cover. My mechanic recommends I replaced it but it’s a couple thousand pounds. He’s recommending I replaced the timing chain and tension mechanism at the same time which will break my cost to about 3500 pounds.  That is just about what the car is worth.. should I repair it or get rid of the car?