8$ Rebuy - early - midgame. Hero has been playing tightish most pots without showndown. Player 5 is essentially all in if he calls the donk lead by Player 3. How do you respond to the donklead?

Seat 1 is the button

Seat 1: Player1 ( 4125 ) - VPIP: 17, PFR: 12, 3B: 3, AF: 0,4, Hands: 84

Seat 2: Player2 ( 2941 ) - VPIP: 17, PFR: 13, 3B: 5, AF: 2,0, Hands: 86

Seat 3: Player3 ( 6520 ) - VPIP: 25, PFR: 11, 3B: 0, AF: 1,4, Hands: 44

Seat 4: Hero ( 6561 ) - 

Seat 5: Player5 ( 1462 ) - VPIP: 23, PFR: 9, 3B: 13, AF: 3,0, Hands: 74

Seat 6: Player6 ( 3810 ) - VPIP: 13, PFR: 6, 3B: 0, AF: 3,3, Hands: 86

Seat 7: Player7 ( 581 ) - VPIP: 0, PFR: 0, 3B: 0, AF: 0,0, Hands: 3

Seat 8: Player8 ( 2981 ) - VPIP: 20, PFR: 13, 3B: 0, AF: 0,0, Hands: 30

Seat 9: Player9 ( 12341 ) - VPIP: 17, PFR: 13, 3B: 6, AF: 2,5, Hands: 198

Player1 posts ante of [20].

Player2 posts ante of [20].

Player3 posts ante of [20].

Hero posts ante of [20].

Player5 posts ante of [20].

Player6 posts ante of [20].

Player7 posts ante of [20].

Player8 posts ante of [20].

Player9 posts ante of [20].

Player2 posts small blind [75].

Player3 posts big blind [150].

** Dealing down cards **

Dealt to Hero [  As Kh ]

Hero raises [375]

Player5 calls [375]

Player6 folds

Player7 folds

Player8 folds

Player9 folds

Player1 folds

Player2 folds

Player3 calls [225]

** Dealing Flop ** [ Kc, 7c, Ts ]

Player3 bets [1050]

Hero ?