Alex Oriakhi is probably the most well-known name available. Because of UConn's sanctions, he is eligible to play next year. The good news: he's from Lowell and would start immediately for BC. The bad news: he supposedly wants to play for a contender, there are questions if he is academically eligible to transfer to BC and he wasn't always on good terms with the UConn staff. Oriakhi is the prize opportunity, but based on his stated needs, I don't see BC in the mix.
Evan Smotrycz is another name to watch. He's a Massachusetts native and played in a system similar to BC's at Michigan. Supposedly he had a relationship with Donahue when Donahue tried to interest him in Cornell. We could use his size, but he will have to sit a year.
Brendan Lane can leave UCLA and play immediately. When he first announced his intentions, there was lots of message board talk about his interest in BC. He would also keep the California pipeline going. But in the week since the announcement, there's been no other reporting. I am guessing it is a long shot.