10NL; 43s BB vs Insane Rier Overbet vs Unknown

No reads or stats on villain. Feel free to critique anything else in the hand, but my primary concern is the insane river over bet from villain. Can we get away with calling this or is this board way too scary?

full tilt poker Game #5244295295: Table Bucyrus-Erie - $0.05/$0.10 - No Limit Hold'em - 19:54:20 ET - 2008/02/13
Seat 1: MC_ShiZZleTM ($10)
Seat 2: happyglen ($1.85), is sitting out
Seat 3: Kissmeyou fool ($2.10)
Seat 4: PierreLeLoup ($6.10)
Seat 5: mloo32 ($14.15)
Seat 6: ingomarleone ($28.45)
Seat 7: royalburrito24 ($10.50)
Seat 8: nolimit1488 ($1.95)
Seat 9: TheCooler211 ($1.75)
ingomarleone has 5 seconds left to act
ingomarleone is sitting out
ingomarleone has timed out
royalburrito24 posts the big blind of $0.10
5 seconds left to act
ingomarleone has returned
MC_ShiZZleTM is sitting out
Time has expired
The button is in seat #5
*** HOLE CARDS ***
Dealt to royalburrito24 [4s 3s]
MC_ShiZZleTM has returned
nolimit1488 folds
TheCooler211 folds
Kissmeyou fool folds
PierreLeLoup folds
mloo32 calls $0.10
royalburrito24 checks
*** FLOP *** [7s 5s 2s]
royalburrito24 checks
mloo32 checks
*** TURN *** [7s 5s 2s] [5c]
royalburrito24 checks
mloo32 bets $0.20
royalburrito24 raises to $0.60
mloo32 calls $0.40
*** RIVER *** [7s 5s 2s 5c] [2h]
royalburrito24 checks
mloo32 bets $4.50
royalburrito24 ??

Can we get away with calling this?

bump bump.

edit: oops typo in title. Should read as "River" not "Rier."

So the pot was $1.4 at the river? You have to call $4.50 to win $5.9 those are not good odds at all, I think you should fold here. He just limped in from late position so he could have a 5 or a 2. Something like K5 with no spade or Ace5 with no spades fits his betting perfectly. All you can really beat here is a missed flush draw or maybe King 7/Q7/A7, but I don't think these hands would make a big bet on the river. Before the river though, you should have bet on the flop so he wouldn't be getting the right odds to call in case he has a big flush draw.

Also, I did not bet the flop because I had a strong reason that he would bet this flop no matter what. I guess I left out the part in the original post where he is the basic fish: Acts strong when he's weak, and weak when he's strong.

easy fold due to scary board on river, please bet flop next time