K8o + blind steal => ???

[Proofrock]

Stars 11+R 45k. No strong read on Villain, except he religiously defends his big blind.

PokerStars No-Limit Hold'em Tourney, Big Blind is t200 (9 handed) FTR converter on zerodivide.cx

SB (t14030)
BB (t12710)
UTG (t24150)
UTG+1 (t23715)
MP1 (t12595)
MP2 (t44102)
MP3 (t4095)
CO (t22698)
Hero (t16375)

Preflop: Hero is Button with 8[img]/images/graemlins/diamond.gif[/img], K[img]/images/graemlins/heart.gif[/img].
<font color="#666666">6 folds</font>, <font color="#CC3333">Hero raises to t600</font>, <font color="#666666">1 fold</font>, BB calls t400.

Flop: (t1200) K[img]/images/graemlins/spade.gif[/img], 5[img]/images/graemlins/heart.gif[/img], 5[img]/images/graemlins/club.gif[/img] <font color="#0000FF">(2 players)</font>
BB checks, Hero checks.

Turn: (t1200) J[img]/images/graemlins/club.gif[/img] <font color="#0000FF">(2 players)</font>
<font color="#CC3333">BB bets t400</font>, <font color="#CC3333">Hero raises to t1200</font>, BB calls t800.

River: (t3600) 6[img]/images/graemlins/diamond.gif[/img] <font color="#0000FF">(2 players)</font>
<font color="#CC3333">BB bets t8000</font>, Hero [img]/images/graemlins/confused.gif[/img]

I raised the turn with the plan of checking behind on the river, but I'm not sure what to make of this huge overbet. Thoughts? Alternate lines? Is it better to fold K8o to a blind defender, or is this fine (i've been raising any hand that is better than 50% against a random hand on the button -- i'd say i've raised probably 1/2 of the time it's been folded to me, but i've only shown down strong hands)?

-J.A.