NL100 set hand correct sized river bet?

[sakrei]

No reads, the reason I posted this is to see if my river bet was the best size. My reasoning is hes calling a shove when hes got me oversetted or folding. This sized bet he calls behind or folds, which seems much safer.
Poker Stars, $0.50/$1 NL Hold'em Cash Game, 9 Players
LeggoPoker.com - Hand History Converter

UTG+1: $89.65
UTG+2: $120.50
MP1: $292
MP2: $121.50
CO: $155.65
BTN: $99
SB: $124.05
Hero (BB): $100
UTG: $99.50

Pre-Flop: 6[img]/images/graemlins/club.gif[/img] 6[img]/images/graemlins/spade.gif[/img] dealt to Hero (BB)
3 folds, <font color="red">MP1 raises to $4</font>, 4 folds, Hero calls $3

Flop: ($8.50) 7[img]/images/graemlins/heart.gif[/img] 6[img]/images/graemlins/diamond.gif[/img] J[img]/images/graemlins/heart.gif[/img] (2 Players)
<font color="red">Hero bets $7</font>, MP1 calls $7

Turn: ($22.50) 9[img]/images/graemlins/club.gif[/img] (2 Players)
<font color="red">Hero bets $17.50</font>, MP1 calls $17.50

River: ($57.50) 4[img]/images/graemlins/diamond.gif[/img] (2 Players)
<font color="red">Hero bets $35</font>