150/300 Stud Hi river

[HOWMANY]

25 ante/50 BI. Villain here seems pretty loose and not so great.

2[img]/images/graemlins/club.gif[/img] BI, A bunch of middle cards fold to me and I complete K[img]/images/graemlins/spade.gif[/img](A[img]/images/graemlins/diamond.gif[/img]T[img]/images/graemlins/diamond.gif[/img])

I complete, he makes it 2 bets. I should call or 3bet?

4th: I catch offsuit Ace, he catches offsuit 7
I bet, he calls

5th: I catch 6[img]/images/graemlins/diamond.gif[/img], he catches a brick that is suited with his doorcard
I bet, he calls

6th: I catch J[img]/images/graemlins/diamond.gif[/img], he pairs the 7 so the boards look like:

(A[img]/images/graemlins/diamond.gif[/img]T[img]/images/graemlins/diamond.gif[/img])K[img]/images/graemlins/spade.gif[/img]A[img]/images/graemlins/club.gif[/img]6[img]/images/graemlins/diamond.gif[/img]J[img]/images/graemlins/diamond.gif[/img]
(XX)2[img]/images/graemlins/club.gif[/img]7[img]/images/graemlins/heart.gif[/img]4[img]/images/graemlins/club.gif[/img]7[img]/images/graemlins/spade.gif[/img]

He bets. I am not sure if he would value bet 2 pair on the river or not if I just called here so I do not think folding to him if I call and miss would be smart. So taking all this into consideration I think a free showdown raise may be okay here?

Even though I'm bad at this game I'm sure that 4-6 are standard. 3rd is too I'd assume.