maybe I'm nuts, but I think the first line of the OP said something like "I JUST BOUGHT THE BOAT"
so any reference to comparative analysis at this point is futile, fruitless, and well, just stoo-pid. Nice or the future, doesn't tell him diddly squat about what he has right now.
And its not hard to look at this type of snapshot and make an educated swag.
That being said, MOST oil analysis(esses) will take the time and point out what the particles contained therein actually "are" boron, copper, bronze,(thrust washers) tin,(coating for thrust washers) lead, chromium (ball bearing surfaces), gunga-munga.
Your tranny is some kind of hurth/kansaki/yanmar contraption so its a std gear reduction unit (I don't think its got many fiber plates & steel separators like an automatic, I may be wrong and I ain't gonna look it up.)
So, IMHO the particulate count might be a hair high, I don't care if its dirt or last months twinkies, it ain't good.
Change the oil, run it a hundred hours and do it again.
The iron count isn't that bad at all, considering your gears are "iron".
and yes, use the smell test.
heres a general guide.
yes, I know the above is for an engine, some of the materials can be in trannys too.