So...Buehrle is 30 years old with 132 wins under his belt. He's averaged 15 wins a year in his first 9 seasons.
He has 168 to go to get to 300.
Obviously, the 300 mark is extremely tough to reach, especially in this day and age. It takes some luck and extreme consistency to reach. But Buehrle has never really been mentioned in the same class as some of the others when it comes to the 300 win conversation (or at least I haven't heard his name).
EDIT...I don't think he'll reach it, I don't know if anyone ever will. But I think he's been under the radar in his career. The highest he's ever finished for the Cy Young is 5th. If he stays healthy he have quite a few career wins when it's all said and done.