Acquiring Dvorak would likely entail mainly dealing future assets (prospects and picks) to a rebuilding franchise; it wouldn’t come cheap, especially if a bidding war for his services occurs. Arizona has no reason to part with this highly effective, cost-efficient middle-6 C and will thus be greedy, rightly so.
I see Copp as a potentially more affordable acquisition since Winnipeg will be tight under the cap after Pionk’s and Stanley’s new contracts and might thus be open to trade Copp (who should command around 4,5M AAV while being used mainly as LW3 since Dubois/Lowry are already sharing middle-6 duties) for a more cost-efficient 3rd liner like Lekhonen and his 2.3M AAV contract - and a small incentive since Copp can play C. It would furthermore enable Montreal to use its futures assets in a trade for a PMD; in that regard, Dunn seems like an obvious candidate.