Toyota Repair: Bad oil leak 1994 Toyota Camry, valve cover gasket, seal leaks

Question
I have a 1994 Toyota Camry with a 3.0, V-6. It has 326,000 miles and a very bad oil leak(s). It uses a quart every 200 miles. I took it to a mechanic and he said the rear valve cover gasket is leaking and also one of the (2)cam seals or the crank seal. He said because of the mileage the engine has excessive blow by and if he fixes the seal leaks the oil would find another outlet or the seals would not last & leak. His esttimate is around $900 including a new timing belt,spark plugs, gaskets and seals. I postponed the repair hoping to get another opinion if the repairs would last for another 50,000 miles on the repairs or should I call it quits on the old girl. The mechanic said it is not worth putting the money into it as it would probably soon leak again. Thank you for your input.

Answer
In this case the mechanic is probably right,at at 326,000 miles it's time to do an engine replacement or just get rid of it, doing minor oil leak repairs may work for a while but I seriously doubt it will last for another 50,000 miles even for a Toyota.