SN member djodenda recently did this, he's very helpful with information.. perhaps PM him.
As for duties, NAFTA eliminated any duties for North American built boats, but watch for French built Beneteaus and others built in the far east. Local taxes and shipping costs should be the only major items to be concerned about.
As a Canadian yourself, are you planning to actually import the boat into the US, or can you keep her Canadian? Not sure about the US rules here and it likely varies state to state...
1984 Fast/Nicholson 345 "FastForward"
".. there is much you could do at sea with common sense.. and very little you could do without it.."
Capt G E Ericson (from "The Cruel Sea" by Nicholas Monsarrat)