1) As mentioned, 600 hands isn't enough for positional 3bet ranges to converge properly. It's safer to make assumptions about his %3bet based on the fact that he's a 11/9 (vpip/pfr converge the quickest of any other two stats) than something else that requires a much bigger sample size and is obviously uncharacteristic (%10 3bet from a %9 pfr player) of this player type. I'd assume it could be more like %7 or 8 max, if even that.
2) Once we establish how wide his 3bet% is, we can derive other conclusions. According to the always-helpful chart in HEM's faq regarding 3bet/4bet game, we know that JJ can be stacked profitably vs a %6.5 3bet range or wider, 100bbs deep.
3) To put it simply, if you don't know what to do postflop, then you likely shouldn't be calling preflop. I've heard better players than myself say "OOP, if it's good enough to call with vs a 3bet, then it's good enough to stack", and I don't disagree.
