Rivered K Hi Flush 5/10 No Limit -- What do you do?

[SILLYGOOSER]

My plan was to check turn and then raise when he bet it. But he checked flop so how would you play on the river?
I've never seen this particulary player before. We've only been in one pot since hes been at the table when I reraised him with ace ace and he made it $390 and then folded to my all in. Since then he's been pretty tight.
Full Tilt Poker Game #4343339907: Table Bayswater (6 max) - $5/$10 - No Limit Hold'em - 4:06:30 ET - 2007/11/30
Seat 1: big work ($4,153.60)
Seat 2: Lady_Sharrow ($990)
Seat 3: SILLYGOOSER ($1,890)
Seat 4: HUGO_BUSTO ($1,000)
Seat 5: sacker ($1,599.45)
Seat 6: browerkid ($2,010)
Lady_Sharrow posts the small blind of $5
SILLYGOOSER posts the big blind of $10
The button is in seat #1
*** HOLE CARDS ***
Dealt to SILLYGOOSER [Kh Qh]
HUGO_BUSTO folds
sacker raises to $35
browerkid folds
big work folds
Lady_Sharrow folds
SILLYGOOSER calls $25
*** FLOP *** [8d Th 9h]
SILLYGOOSER checks
sacker checks
*** TURN *** [8d Th 9h] [6d]
SILLYGOOSER has 15 seconds left to act
SILLYGOOSER bets $65
sacker calls $65
*** RIVER *** [8d Th 9h 6d] [7h]
SILLYGOOSER has 15 seconds left to act
SILLYGOOSER bets $180
sacker has 15 seconds left to act
sacker raises to $480
SILLYGOOSER ?????