Marginal Turn Decision: 5:1 with a weak draw

[TheRempel]

PokerStars Pot-Limit Omaha High, $0.50 BB (9 handed) converter

saw flop|<font color="#C00000">saw showdown</font>

BB ($16.90)
UTG ($25.75)
UTG+1 ($63.15)
<font color="#C00000">MP1 ($11.10)</font>
MP2 ($41.45)
<font color="#C00000">MP3 ($16.05)</font>
CO ($44)
<font color="#C00000">Hero ($409.25)</font>
<font color="#C00000">SB ($105.55)</font>

Preflop: Hero is Button with 5[img]/images/graemlins/spade.gif[/img], 7[img]/images/graemlins/diamond.gif[/img], 5[img]/images/graemlins/club.gif[/img], 6[img]/images/graemlins/club.gif[/img].
<font color="#666666">2 folds</font>, MP1 calls $0.50, <font color="#666666">1 fold</font>, MP3 calls $0.50, <font color="#666666">1 fold</font>, <font color="#CC3333">Hero raises to $2.75</font>, SB calls $2.50, BB calls $2.25, MP1 calls $2.25, <font color="#CC3333">MP3 raises to $16.05</font>, Hero calls $13.30, SB calls $13.30, BB folds, MP1 calls $8.35 (All-In).

Flop: ($62) Q[img]/images/graemlins/diamond.gif[/img], 3[img]/images/graemlins/club.gif[/img], 8[img]/images/graemlins/diamond.gif[/img] <font color="#0000FF">(4 players, 1 all-in)</font>
SB checks, Hero checks.

Turn: ($62) 2[img]/images/graemlins/club.gif[/img] <font color="#0000FF">(4 players, 1 all-in)</font>
<font color="#CC3333">SB bets $15</font>, Hero ?.</font>

SB is a calling station, doesn't seem to understand the game. (He bets with hands like TJQK on 444T5 boards, and he's not bluffing).
MP3 is a habitual shot taker.

What's your turn action?