I really don't think the Leafs can support that cap hit without moving one of their top guns. Imagine all of the picks/prospects that Arizona could get, but I don't think the Leafs have that kind of draft capital in comparison to other teams possibly in the mix for Chychrun (nowadays, I've been hearing Kings or Bruins, but that's probably an offseason thing to look at, not at the deadline).
Why the hell would the Leafs want Binnington @ $6M AAV for the next 5 years? Even if it's only at 50% or 25% of his cap, Mrazek is already signed for 2 more years, and I don't see how the Leafs are going to walk away from Campbell - he loves it here, the team/fans love him. Though personally, I'd love it if they could unload Mrazek - that's one signing that did not work out as planned.
All of the *real* insiders (Friedge, Dreger, Lebrun, Johnston) ... none of them have uttered Binnington's name in the last 2 weeks, and they're all still under the belief that Dubas is more likely to go after defence, not goaltending.
As for their cap space ... if they keep Muzzin on LTIR until the playoffs (concussion issues), they've got room to manoeuvre.