Honestly dunno. On one hand he's still real gud. On the other hand he's signed for 6.25 x 3 after this season. When I look for similarish defenders moved recently, Tampa gave McDonagh away, Montreal got Matheson (a decent #3-4 in his prime) and stuff for Petry. Our original Muzzin trade is another similarish move. The values are kind of all over the place.
If I was spitballing, I'd say that we're probably somewhere in the realm of Sandin + prospect (Niemela?) + Salary/Kerfoot with no retention. Dude is good, but he's also 33 and the contract is a thing as well.