CVS Health Corporation (NYSE:CVS) is exploring an acquisition of Oak Street Health, Inc. (NYSE:OSH) according to people familiar with the matter.  A deal could be reached within weeks that would value Oak Street at more than $10 billion, including debt, said the people, who asked to not be identified because the matter isn't public. Talks between the companies are ongoing and could end without an agreement, the people said.  Representatives for CVS and Oak Street declined to comment.