He is currently 6th in the AL in WAR. He has never finished in the top 10 before and he is 36 (or was as of June 30). Off the top of my head, I can't think of anyone who might have cracked the top 10 for the 1st time so late in his career. Who else might have done something like this?
He has 5.1 and 10th place has 4.7 (Pujols). So with only 5 games left, it looks like he will make it. His highest WAR before this was 5.0 in 2009.
For ages 36 and older, a WAR of 5.0 or higher has only been reached 47 times. Randy Velarde was 4th in the AL in 1999 with a 6.7 at age 36. It was his only top 10 finish ever. I think his next best year was 3.2.
Al Oliver made it for the first time in 1982 at age 35. He was 10th in the NL with 5.7.