Oops, I said the noise was only on startup. What I should have said was only on the first cold start in the morning. Quiet as a church mouse the rest of the day.

 

Yup, sounds like the lifters are bleeding down during the night.
You can try flushing the engine and use a heavy weight oil and see what happens. The only other thing is to replace the lifters.

With that mush mileage have you tried adjusting the valves? They could be worn enough to cause a little extra slop.