I have done the theory #4446 (blablabla). But I have to correct many mistakes.First , im not going to pay attention to the photo I have seen. So lets discover who is RJ.

List of the SEVEN SUSPECTS:

-Brett Patridge
-Bob Kirkland
-Thomas McAllister
-Reede Smith
-Gale Bertram
-Bret Stiles
-Raymond Haffner

Clue #1: Red John kills people that investigate him. The only one that can do this is Patrick Jane.
So , if we count that , Bob Kirkland can´t be.
Now , the list is like this:

-Brett Patridge
-Thomas McAllister
-Reede Smith
-Gale Bertram
-Bret Stiles
-Raymond Haffner

Clue #2 Lorelei told Patrick that Red John hadn´t became friends since they shaked hands.So , Bret Stiles  cant be , because he is Patricks´s friend.
Now the list is:
-Brett Patridge
-Thomas McAllister
-Reede Smith
-Gale Bertram
-Raymond Haffner

Clue #3: Roselind Harker told Patrick that Red John is less than 6 fit tall:

Brett Patridge: 5 ´11
Thomas McAllister: 6
Reede Smith: 6´3
Gale Bertram:6´3
Raymond Haffner: 6´1

Only leaving:

Brett Patridge
Thomas McAllister

Clue #4: Red John´s best friend was a Sheriff (1x23) isnt it a coincidence that Thomas McAllister , one of the suspects , is a Sheriff. We dont know if he worked on Vizualize , so perhaps it could be Raymond Haffner.

BUT KNOW ... SHERIFF THOMAS MCALLISTER IS RED JOHN (OR RAYMOND HAFFNER)