Just one word of warning on the OEM parts; get ready for sticker shock.
I did my timing belt and water pump replacement a couple of years ago and used all stock components. It was EXPENSIVE, compared to some of the Ebay kits, but I figured since the first set lasted over 100k then the second set should last just as long.
"The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong, it usually turns out to be impossible to get at or repair."
-Douglas Adams, Mostly Harmless