I did this a couple months ago. If its an ALH, the seal can be had via the stealership, because the coolant pipe should be ordered by VIN number of your car. It's like, 80 bucks. There are two seals, round or square in section. Which one you need depends, again, on your vin number. The rubber seal is another $2.50 or so.
As for the copper washers, you can reuse them. First, however, you must anneal them. Heat them up to glowing red and drop them into a container of cold water. This softens the copper so it seats again. When you torque down the oil fitting it will work-harden the copper, but it can always be re-annealed in the future.
The only trouble I had doing this was coming to grips that I had to dismantle half the engine compartment to get the damned thing out. Then puttting the new one in almost drove me insane. I ended up cutting the electrical connector bracket off the front, getting the pipe in, and then welding the bracket back on. It was easier than trying to shoe-horn it in there with that on it. If you're over that step, good on ya. If not, well, there you go. Hope you have a welder.