Due to needs and cap restrictions, if there was a trade to be had Fowler would probably cost, minimum, Lehkonen+1st or Lehkonen+2nd + juniors prospect.
Ducks need LW and Lehkonen has so far shown he's NHL ready and capable. He's LW, on his ELC so cost controlled, and the pick (and junior player) offset the remaining value.
Would I do it from a Habs perspective.... maybe, if there was a plan already in place to fill Lehkonen's slot.
But as was stated earlier, the Ducks seem as if they are planning on keeping their current roster at least for now, though things could change with the right offer or a change in circumstances in Anaheim.
But as I stated in the OP, for me Fowler is the best choice for the need and fit.
The rest, have their merits, but my biggest question is...
Does anyone consider Beaulieu or Emelin Top 4 D?
If so, there are talks to be had.
If not, the Habs are out on any trades requiring a top 4 D in return.
Would be nice if it's Emelin moved so Beaulieu can stay, but that 4m cap hit is hard to move, which is weird because Emelin is a force to be reckoned with. He's not as physical as he used to be, but when he hits... boy does he hit.
Best case scenario is Emelin is traded and Desharnais is waived to make cap space.
Lastly, everything depends on whether MB is looking for a short term fix or a long term keeper.
Short term, I like Scandella, Edler, Staal.
Long term, Fowler, Brodin, Gardiner
Not a consideration is Trouba. Wants to much money, wants to play the wrong side, wants to play in the US.