What would you do? #85 - Facing rivered paired board shove with nut flush

Rush poker, no reads:

Full Tilt Poker $0.50/$1 No Limit Hold'em - 9 players
The Official DeucesCracked.com Hand History Converter

UTG+1: $115.90
UTG+2: $53.05
MP1: $32.40
MP2: $88.40
Hero (CO): $106.40
BTN: $41.50
SB: $108.55
BB: $57.75
UTG: $236.75

Pre Flop: ($1.50) Hero is CO with Ah 2h
5 folds, Hero raises to $3.50, 1 fold, SB calls $3, 1 fold

Flop: ($8.00) 9s 7h 4h (2 players)
SB checks, Hero bets $5, SB raises to $15.50, Hero calls $10.50

Turn: ($39.00) 6h (2 players)
SB checks, Hero bets $20, SB calls $20

River: ($79.00) 7c (2 players)
SB checks, Hero bets $25, SB raises to $69.55 all in, Hero requests TIME, Hero ???


Click to see results

What would you do in this spot? I think, in retrospect, this is an easy fold. He played it exactly like he had a set.

Hero calls $42.40 all in

Final Pot: $213.80
Hero mucks Ah 2h
SB shows 4s 4d (a full house, Fours full of Sevens)
SB wins $210.80
(Rake: $3.00)