There isn't a ton I want as far as firearms go but a real, old school lever action cowboy rifle would be right up my alley. It would look very nice underneath my 1946 Lee Enfield No4(T).
You MAY have to hire the services of a firearm importer to do this legally. I haven't done much looking into transporting an unrestricted across the border into the States but as a Canadian, if I wanted to buy one in the States I would need someone with a licence to import firearms to get it. Wouldn't surprise me in the least if this was true for Americans too.
http://canadiangunnutz.com/
TONS of info in this sight regarding transportation legalities. You will need to sign up though.