Christine,
Nice to hear that you are heading to the US again. Another option not yet mentioned is the Oregon Coast Trail. It’s about 450 +/- depending on how you do the water crossings. You can easily extend down the California Coast Trail for another 120 miles. If you comfortable using a pack raft, you can eliminate a lot of road walking.
There are pluses and minuses on this route. A bit more road walking than one might want, but lots of nice small towns and easy resupply, and lots of very fine beaches. We have a lot of details at https://doingmiles.com/2008-07-oregon-coast/
Contact us directly if you want more info.
best regards, James and Amy