We were looking at Silversea cruise to the Arctic
They provide a package you can purchase plus provide a parka
I would check if they do the same before you go spending $$
Check list here.
Found this site they have Le Boreal on the list of ships they supply see here.
Edited to provide links.
Alexandr Pushkin, Carnival-Holiday, HAL-(old)Westerdam, Orient lines-Marco Polo, Royal Olympic-Olympic, NCL-Dream, Dawn-Princess, ACCL-Grande Caribe, Oceania-Insignia (3), Regatta(4) Marina (1) St Lawrence Cruise Lines-Canadian Empress
Scenic River cruise June 11,2012