25nl AK too passive?

[spyderracing]

What's your move here, and what's your move if he open shoves?

Opp is 22/3/??(where do I find AF on PT?) but only over 28 hands so I'm not sure the stats really matter at this point, but he's basically been semi-loose passive.

PokerStars No-Limit Hold'em, $0.25 BB (9 handed) internettexasholdem.com

MP3 ($17.70)
CO ($31.20)
Button ($14.65)
SB ($26.60)
BB ($9.65)
UTG ($27.40)
UTG+1 ($5.10)
MP1 ($15.90)
Hero ($25.30)

Preflop: Hero is MP2 with K[img]/images/graemlins/diamond.gif[/img], A[img]/images/graemlins/heart.gif[/img].
<font color="#666666">3 folds</font>, <font color="#CC3333">Hero raises to $1</font>, MP3 calls $1, <font color="#666666">1 fold</font>, Button calls $1, <font color="#666666">2 folds</font>.

Flop: ($3.35) 5[img]/images/graemlins/diamond.gif[/img], K[img]/images/graemlins/spade.gif[/img], 8[img]/images/graemlins/diamond.gif[/img] <font color="#0000FF">(3 players)</font>
<font color="#CC3333">Hero bets $3</font>, <font color="#CC3333">MP3 raises to $8.75</font>, Button folds, Hero ???

Final Pot: $15.10