Hello everyone, I'm new here, just opened an account and already I have a “crazy bluff” question.

The tourney is a sunday 100$ with rebuys on merge network, 11 players left deep in the money.

Merge, $100 Buy-in (6,000/12,000 blinds, 1,200 ante) No Limit Hold'em Tournament, 6 Players
Poker Tools Powered By Holdem Manager – The Ultimate Poker Software Suite. View Hand #8546032

UTG: 316,092 (26.3 bb)
MP: 191,138 (15.9 bb)
CO: 311,237 (25.9 bb)
BTN: 120,716 (10.1 bb)
Hero (SB): 455,455 (38 bb)
BB: 587,573 (49 bb)

Preflop: (7,200) Hero is SB with 5 5
4 folds, Hero raises to 33,000, BB calls 21,000

Flop: (73,200) A 7 3 (2 players)
Hero bets 48,725, BB calls 48,725

Turn: (170,650) 7 (2 players)
Hero bets 112,375, BB calls 112,375

River: (395,400) J (2 players)
Hero checks, BB checks

My thoughts: I was planning on 2 barreling this board cause his flop
calling range is very wide: Ax, 7x (3x?), underpairs, flushdraw,
gutshots and mb even floats with air, cause the board is so good for me
to cbet and he is in pos. – so on the turn we should get huge amount of
folds, and the only calling hands shuold be: a. monsters (trips+), b. Ax
– narrow range: “AT-” – cause higer A would have 3b pf , and “A8+” –
cause with hands like A2 he beats nothing except flushdraws (he may have
A5,A6 – he may be weak enough to call with them, I don't have much
experience to determine that) and bluffs; c. flush draws – seems to be
unlikely, cause it's on the turn and the board paired (but who knows ).
The questions is whether to fire 3rd barrel on riv or not. I chickened
out and checked, main reason being, that I was hopping to be against
very narrow Ax range after betting the turn + FD came on the riv, so my
push doesn't fold too much. But now thinking about it, it's probably
much better to shove: 260k into 395k pot, must work ~40% of the time to
make it profitable. A8-AT make 36 hands already (and he may have more
Ax) so he should have 50+ calling hands to make my shove -EV. 77,A7, 33,
7x(87s,76s,K7s lets say) = 16 hands, even adding some flush draws won't
change it too much. The only problem may be if he's calling the push
with Ax, but he really shouldn't: my line doesn't look like Ax( AK for
example will not be betting the riv), but it fits for 7x and FD's that
hit on the riv, so he beats only 3brl bluff. Also there is the final table bubble effect which may encourage him to fold more.

What are your thoughts, guys? Opinions about any of the mentioned ranges and op's tendencies will be highly appreciated.
Hope that the post wasn't too long  

Thanks all