at this point in the investigation we can surmise these things....the item isnt govt.issue.the ship he served on was involved in many historical missions and actions.He was not,BIG on celebrating his service.
I submit this guess....the item was commisioned by a veteran group,likely in advance of a reunion or the like.Being a humble man he simply accepted the item and stowed it.It is a comercially made item.
add it all up and I say that I wish he was my neighbor or friend.A great man