I posted these lines earlier, and barring injury, I don't think Berube will stray too far from them, at least at the start:
Again, I use the asterisk for Blais and Steen because it's quite possible Blais goes on the fourth line and Steen on the third. This lineup would have Kyrou and de la Rose as extras.
Bortuzzo as an extra
That's a 23-man roster of 21 skaters and 2 goalies. So with an anticipated 28-skaters on the playoff roster, I think they would come from this pool: Brouwer, Kostin, Nolan, Poganki, Walker; Mikkola, Pouliot, Walman. (It doesnt look like Perunovich will be eligible to play this year out of college.)
If the Blues keep 4 goales, it would most likely be Husso and Wilcox.
Over a month ago, Armstrong provided a pretty good blueprint in the Post-Dispatch of what he's looking for in terms of extras/callups. (Note: He also mentioned Toropchenko in this story.)