If Perron is out longer

According to Lebrun via the athletic we've agreed in principle to a 5 year deal with Silf that can't be signed until some cap is moved out

"You can take his name off any trade list.
Sources suggest the Ducks and Silfverberg have essentially come to an agreement on what will be a five-year deal but it can’t be signed and made official at this point because of tagging issues the team is dealing with.
It’s not clear when exactly they can get the contract signed. But what’s clear is that any team calling Anaheim on Silfverberg is being told he’s not available."

And in a deal he is moved we wouldnt retain or have to retain anything to get a good return

They’re gonna sign him but I’m starting to think we need Perron insurance

Personally, I think we need some speed and slightly more skill. This run is great and everything thankfully in part because of great goaltending, but if Armstrong wants and feels like we have a shot at the cup this season he needs to get more speed into that lineup. Even though we beat both Tampa and Toronto, even though we beat Nashville in back to back, it's clear that other teams' speed is going to be hard for the Blues to contend with over the course of 7 games. Blues looked tired especially in that second period and the speed factor of the other team's led to some bad decisions with the puck in our own zone. We sat back on our heels, blocked a lot of shots still, but we have Toronto the opportunity to come back. Not sure what Armstrong will do, but we need to get in a second line center, hopefully Thomas can take that spot, but assuming Perron comes back and Thomas is not ready, we need someone other than Bozak in that 2nd line center slot.

johansson, zuccarello and dzingel i think are three good options

I think if we do anything we should go big. Adding to the top of the lineup pushes everybody down into rolls they can excel at and can help mitigate the lack of elite talent. I beleive Perron is a 3rd-liner on a cup team but his return will certainly give Schwartz a boost. I’ve seen talk of adding a 2c or a PPqb but honestly I think we already have both (Dunn, Thomas.) I love Berube but my one gripe is that Pietrangelo is on PP1 instead of Dunn. If we burn assets and cap on a QB while we’ve got a 22 year old on a 38 point pace playing 17 minutes I will be pissed.