I discovered meaning for all those letters. I'm not sure about a year, that label is missing. I think Yamaha don't mark a year of production with a letter since 2005.
But when I search for spare parts on Yamaha web, there's no sequence "F9.9FMH" in drop down list
As for the Yamaha website, try using F9.9F in the drop down as you'll find it also pulls through combinations of the other characters when you hit the search button