TORONTO, Nov 4 (Reuters) - Canadian insurer Sun Life Financial Inc beat analyst estimates for third-quarter core earnings on Wednesday, boosted by growth in income from Asia and its asset management unit. Sun Life reported underlying profit, excluding charges, of C$842 million ($641 million), or C$1.44 a share in the three months ended Sept. 30, compared with C$809 million, or C$1.37, a year earlier. Analysts had expected C$755 million, or C$1.28 a share. Reported net income rose to C$750 million, or C$1.28 a share, from C$681 million, or C$1.15, a year earlier.