Website will, likely show the latest version of the boat. If your hull plate says 2.5Tonnes / 4.5Hp, than that's what your insurance will be basing it on, even although the hull may have been redesignd ten times between the one you have and what you see on the website and wander over the bridge to buy new.
I don't know when your hull was made, but a wee example,, mine was built in 1984. Even Autolube hadn't been invented and most 60s were 2 cyl instead of 3 and so my transom is rated to 110Kg / 60Hp. I'd be pushing it with an Autolube 60Hp Yam! (one of the reasons I have my museum hanging on the transom)
As a good rule of thumb, work out from the plate when it was built, and if it says 80Hp, than at a going in point most 80Hp engines of the time will be spot on for a max engine.
If your hull was built before 2- stroke was banned, any 4- stroke will likely put your transom top precariously close to the water!
Or you could wander over to the dark side & get a nice light 80Hp Clamshell......