I have a very old book 1985 "Oregon Coast Hikes by Paul M Williams (Photos by Bob & Ira Spring [deceased - the brothers wrote some of the best hiking guides for WA) At the time he said just 62 miles of the Oregon Trail was done.
William Sullivan writes allot of hiking books on Oregon ad one is
100 hikes /Travle Guide Oregon Coast & Coast Range 2009 probably a newer version out by now.
He says only about 75 miles is actual trail (which is probably good as some of this has no views 85 miles follows roads (101 for instance)
He notes with a symbol in the contents page which of his hikes cover a completed portion of the "trail:", and in the text he uses the same symbol in the margin to show where he briefly mentions the coast trail (directions like it is on the beach all the way to Gearhart).
Backpacking Oregon by Douglas Lorain describes 2 sections out of 27 trips in Oregon. Seaside to Manzanita & Port Orford to Bandon
But the linkss above look better and more upto date , though this does give suggestions of things to see etc.
This section requires fords at sixes and new river. New river emptied into the Pacific at 4 mile creek, but the link above shows it further north, and an interpretive sigh shows it even further north at 2 mile creek. I wonder if the ocean still pours in at the former sights? Did it move back which is the most recent? I probably should have waited but after the dentist put on my crown I wanted to get away.
I camped at Beverly Beach, and it rained pretty hard even though the forecast said light, and harder rain was coming, I had 2nd thoughts about trying the crossing, since it would not be absolute low tide (negative) but half way between low and high. It cleared up on the drive down so I decided to enjoy the sun and stopped at view points along the way and it was much later than I hoped, and it was really blowing in Bandon, making it rather cold in the middle of the day. So I decided to car camp that night.
I tried to drive into 4 mile creek but it says no parking now so I went to the next place over and saw the sighs about the new rivers mouth moving. The next day I decided to go into floras lake and hike around and over to black point, Not sure which would be better at low tide I think one book said you could try the slippery rocks at low tide - don't remember for sure, but the trail was good but wound around quite a bit. I car camped at Cape Blanco the trail up to it from the south should be pretty obvious, you can drive quite a ways down tot he ocean from the campground. I stopped at the light house and luckily saw a gal with her dogs coming back up from the north side. I was going to dayhike it the next day, but it was all foggy that morning , (and wet and windy I forget now) so I drove on to Bandon which was partly sunny by then. . .
So not sure when one would reach the stream crossing (timing for low tide?). or how hard it might be now that is has changed. Not sure if the trip reports talk about this, would look at that if I decide to try again in better weather with low tide more in the middle of the day.
But I think I saw a fair amount of it even if I did not experience the adventure of it. Oh one book talked about the (confusing?) trails around the airport and a gal came there to black point, but not sure why a thru hiker would go that way. (One book said it was a shorter, if less scenic way to black pt). Very windy there wondered if a wind surfer on the lake would be ok.