I thought Halladay might have a shot too when I was first thinking about it. But I doubt it and here's why.
He just turned 32, and yes he's at 140 wins right now. But that's including the 9 wins he already has this season. So if he wins 20 games this year, he'll be at 151. It would be his third time winning 20 games, doing it also in 2003 and 2008.
If he's at 150 going into next season, that's 10 more seasons averaging 15 wins to make it. In his career (10 years) he's bested 15 wins 5 times. And he hasn't averaged 15 wins to this point, when he's in his prime.
I just don't think he'll get there, at least not if he stays in Toronto. They won't be able to provide him with the offense to do it for 10 years. Last year he had 20 wins but had 11 losses, with a 2.78 ERA and a 1.05 WHIP. He's right on pace with those numbers this season, but he's getting help from the offense and has only 1 loss.
I think the only way he's got a shot is to win like 27 games this season and get out of Toronto ASAP.