(NL50) Good spot for blocking bet on river?

[JoshNjuice]

No read on villain. I just stacked another player last hand (KK > AKo, all-in PF). I've only been at the table for maybe 7 hands or so.

PokerStars No-Limit Hold'em, $0.50 BB (5 handed) Hand History Converter Tool from FlopTurnRiver.com (Format: 2+2 Forums)

Button ($30.15)
SB ($8.70)
BB ($133.90)
UTG ($78.20)
Hero ($95.75)

Preflop: Hero is MP with T[img]/images/graemlins/spade.gif[/img], 8[img]/images/graemlins/spade.gif[/img].
UTG calls $0.50, <font color="#CC3333">Hero raises to $2.5</font>, Button calls $2.50, <font color="#666666">2 folds</font>, UTG calls $2.

Flop: ($8.25) 4[img]/images/graemlins/spade.gif[/img], T[img]/images/graemlins/diamond.gif[/img], J[img]/images/graemlins/diamond.gif[/img] <font color="#0000FF">(3 players)</font>
UTG checks, <font color="#CC3333">Hero bets $5.5</font>, Button calls $5.50, UTG folds.

Turn: ($19.25) 4[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(2 players)</font>
Hero checks, Button checks.

River: ($19.25) 5[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(2 players)</font>
Hero ???

Should I block this river for about $5 or $6?