7.5hp convert to 10hp

[electricalbob]

Not a new one this, Can I convert a 7.5hp merc into a 10hp by fitting another carb? The engine serial no. is 9202012, its of Belgian origin, the carburetor has "Mercarb" on it, can't see any number though.
What year is the engine pls, many thanks.

[boats.net]

Might could but we don't alter horsepower on engines and don't know what it would take.