Depends on the team.
Unfortunately, a lot of teams that need a #1 goalie (NJ, NYI, PHI, PIT, although they are sticking with Fleury — good luck there
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) are in our division, and, obviously, the Rangers aren't trading Lundqvist to a rival.
I could see Edmonton, Minnesota, St. Louis, Tampa Bay, Toronto, and Winnipeg being heavily interested.
The return, obviously, would have to be substantial — even with a year left on his deal, Lundqvist is arguably a top-5 player and has been the team MVP nearly every year in his tenure. It would have to be something like:
Top-6 roster player x 2 or a top-6 roster player and a top-4 D
Top prospect
1st
Similar to the Nash deal. I don't know if the Rangers would get it, but teams would certainly pay a hefty bundle to get the best goalie in the NHL, in his prime.