Master 410 aluminium boat with Yamaha Autolube 20hp 2-stroke engine

Russian made full aluminium boat Master 410, manufactured 2006. The engine is Yamaha autolube 20hp 2-stroke, year model approximately 1991. The washer in the exhaust pipe has been drilled larger, so the true hp should be around 25hp. The propeller is 1" larger than it should and one blade is a bit bent. Total load including the engine is about 250kg.