Commerce 10-20 NL Hand 3 of 3

[Ulysses]

I have everyone covered. My opponent has about $1400. Neither of the other guys in this hand have very big stacks. He seems very straightforward and neither particularly good or bad. Pretty easy to read, slightly on the weak side, and I haven't seen him get out of line yet, but we haven't been playing too long. All-in-all, I think straightforward sums him up pretty well.

I limp w/ 77 in EP. He calls. Wacky/tricky/strange guy calls. SB calls. JA Sucker calls in BB.

Flop is 789 (I don't remember if there was a flush draw)

$100 in pot. I check. He bets 30. Wacky guy calls. Sucker calls. I make it $200. He now immediately says raise. He thinks a second and raises to $800 straight. He has $600 behind. Other two guys fold. What now?