77 in SB vs. 3 bet by BB

[MexKrax]

Villian in this hand is a little passive 33/8/1.

Party Poker 5/10 Hold'em (6 max, 6 handed) FTR converter on zerodivide.cx

Preflop: Hero is SB with 7[img]/images/graemlins/diamond.gif[/img], 7[img]/images/graemlins/spade.gif[/img].
<font color="#666666">4 folds</font>, <font color="#CC3333">Hero raises</font>, <font color="#CC3333">BB 3-bets</font>, Hero calls.

Flop: (6 SB) 6[img]/images/graemlins/diamond.gif[/img], K[img]/images/graemlins/club.gif[/img], 8[img]/images/graemlins/club.gif[/img] <font color="#0000FF">(2 players)</font>
Hero checks, <font color="#CC3333">BB bets</font>, Hero calls.

Turn: (4 BB) 2[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(2 players)</font>
Hero checks, <font color="#CC3333">BB bets</font>, Hero calls.

River: (6 BB) 5[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(2 players)</font>
Hero checks, BB checks.

Final Pot: 6 BB

Was calling down here the right play? I figured 77 was a resonably good hand so I want to see a showdown here, but it's not too strong so I want to get there as cheaply as possible right?