Joined: Jul. 2021
I don't think you're going to get much for Rielly in a trade now if he's not willing to sign an extension. They might have been able to get more earlier in the off season (though the Ristolainen trade was unprecedented), but most teams have already assembled what they think they need for this season.
As a 1-year rental he's of no interest to a rebuilding team. You might get a pair of 2nd round picks or a 2nd and a prospect from a contending team, but then the Leafs would probably have to keep half of his salary since most of those teams are already at the cap. If they want a roster player it would be either another rental (can you name one who would help them more than Rielly?) or a younger 3rd-pair guy who may still have some upside, but that would be a downgrade for this season and I don't think that's what the Leafs want. I don't know what Dubas has said and whether it's the truth or just a tactic to try to convince Rielly to sign an extension, but the fact is that one year of Rielly is worth more to the Leafs than anything they could get for him in a trade.
The only scenario that makes sense to me would be if they could trade him for picks and prospects and then flip those picks and prospects along with more picks and prospects for somebody who could be a longer-term replacement for him. Chychrun would be nice, but I'm not sure the Leafs could assemble enough quality picks and prospects to get him.