The site
http://buckieheritage.org/old-snippets/ has all sorts of Reids, Reaich, Farquars, etc but not William Alexander and Maggie that I could find.
I had better luck at
http://www.nationalarchives.gov.uk using the search terms merchant seamen. It directed me to
Merchant seamen registers 1918-1941 which are at findmypast.
Not only was William there, but it had a picture of him! The form itself is called a CR10, and unfortunately on his, as well as all the other ones I looked at, the next of kin line was never filled out. It is him though, as his birthdate and place match perfectly.
It does give his discharge number, and after a lot of reading, I have found that the discharge number isn't a discharge from service, but the lifetime number used when discharged from one ship to move to another ship. As in, every time they sailed a different ship, they would use the same discharge number on the paperwork for their lifetime.
Somewhere at
http://www.nationalarchives.gov.uk and various forums, I read that there are files that you can track people by this discharge number, but many files have been lost over time. You may want to ask the Archives about that, or perhaps try asking on the forum at
http://www.shipsnostalgia.com/showthread.php?t=29807 (look at the first reply, might be some help in there).
Another lead to follow might be the recent death (2016) of a James Reid. I found him looking through Scotlandspeople's deaths of Reids with a mother with a maiden name of Reaich, and he was the only hit. He was 93, and death registered in Elgin Moray. Maybe you can find an obit; I had no luck, but admittedly didn't really know where all to find Scottish obits. I also tried to find a birth for him, but there was far too many, with several in Rathven, same place that William and Maggie married, if memory serves.
If you can't access the file with his picture, pm me an email address if you would like to see it.
