I'd shop Clarkson and Greene together. I love Clarkson but his stock is at an all time high scoring 30 this year. He literally got every single break to go his way. His next contract is going to be huge. Greene has a decent contract and is a top four defensemen.
Maybe the both of them for Bobby Ryan. Like others have said, I think it's going to be an off the radar move.
And every GM knows that about Clarkson...they probably think he's a bit of a fluke, so his stock probably isn't as high as one might suspect. And he's a pending UFA to boot. Devils are probably better off hanging onto him.