I don't know what you could expect to pay for the dealer to change the PCV elbow. I'm guessing probably somewhere around $300 based on the 2 hours or less labor and the $25 part marked up by 40% or so. The intake manifold gaskets are reusable if I remember correctly.
Other items you should consider while in there would be spark plugs and, if the plugs/coils show evidence of oil leaks, valve cover gasket sets and coils. The bank 1 spark plugs are very easy to get to once you get the upper intake manifold off.
-Rod