75/150 LIMIT (seriously) Omaha Hi river play

[HOWMANY]

Yes there are people dumb enough to play this game in minbet form. Crazy Mike wants to play it so we play it. Game is 4 handed, villain is Crazy Mike. Despite his name he is not particularly crazy and is fairly straightforward, which is why I found this spot so confusing.

CO limps, villain raises button which means that he started with 4 cards that are reasonably connected in some way. I call in the SB with 5[img]/images/graemlins/club.gif[/img]6[img]/images/graemlins/club.gif[/img]7[img]/images/graemlins/heart.gif[/img]7[img]/images/graemlins/diamond.gif[/img], BB calls.

Flop: A[img]/images/graemlins/club.gif[/img]J[img]/images/graemlins/diamond.gif[/img]7[img]/images/graemlins/spade.gif[/img]
I bet, SB and CO fold, villain raises, I 3bet, he 4bets, I call now prepared to call down and get shown a better set.

Turn: 5[img]/images/graemlins/spade.gif[/img]
I check, he checks. Now it seems my hand must be best.

River: 5[img]/images/graemlins/heart.gif[/img]
I bet, he raises, I can only call here I think especially considering I hold a 5 I think? I guess it's not out of the question that he 4bet the flop with like 89T5 and took a free card but it doesn't seem very likely or consistent with his normal play.