I wandered the Pacific northwest coast for years. I haven't gone out of my way to find piers, but I'd say most of the Oregon coast fishing towns would offer possibilities (both sport and commercial operations). I would think that you'd be more likely to find them in harbors and at river mouths, rather than right at the ocean shoreline. You might find good pickings in Eureka, Astoria, Aberdeen. Have you tried zooming in on Google Earth?
Good luck!
Merrill