Hi,
Sadly, the intake manifold and cylinder head on those is all one cast piece.
It wouldn't be impossible for a gifted fabricator/TIG welder/machinist to restore that carb mount ear but I doubt that it would be an affordable proposition.
The good news MIGHT be that, since the 9.9hp Honda is likely one of the most sold 4 stroke outboards in the world, my guess is that there are lots and lots of "fixers/parters" out there if you just look and have patience in your search. I'm not 100% sure but I think that, your's being a 2007, your year model choices probably run from 2003 up to and possibly beyond 2020.
Checking with an authorized dealer's parts department for cross referencing the numbers would be advised over trusting my guess about that.
Wish I had better news for you but as me old pappy used to say, "it am what it am"....
...or something like that.
Just remember, whichever way you go in making a repair, it was likely in the 99.9% range that OVERTIGHTENING the carb mounting bolts is what caused that ear to break off.
A real shame (along with the unfortunate design choice) that it happened.
These are truly fantastic little twin outboards and well worth saving. I own it's big brother BF20D. It has the exact same head design and I wouldn't hesitate to to effect a repair if this were to happen to me.
I FEEL YOUR PAIN THOUGH!
Good luck.
