I'll tackle the oil leak issue on mine next week.
My old faithfull 260E will have a new head gasket, valve guide/seals job, front engine cover, valve cover gasket and rad.
full tune-up (plugs, wires, distributor cap, rotor), all new fluids, 4 new shocks absorbers, some suspension bushing replacement 4 new tires,(MichelinMXV4) wheel alignment, front brakes. etc.
The car has only 341,000KM (211,000mi).
This is still cheaper than getting a new car.
JackD