Hi, Nigel!
I am not a professional coin authenticator, but given my nearly 25 years of experience in the numismatic arena, I have reason to believe this piece may be counterfeit or altered due to several diagnostic concerns. The appearance of the date and certain elements of the design look off for the issue. I think the surface also looks rather unusual for a circulated Morgan dollar. These are things that could be better inspected in-hand by an individual who can weigh the coin, look at it from different angles, and apply a good degree of sight-seen evaluation. Perhaps the piece will check out as authentic, but I do want to give you the heads up that, given what I see, this coin is at best altered and possibly a complete replica.
All my best,
Josh