Good thread, been thinking about GOT typology a lot in my sleep.

Lets start with the strong possible NFs and NTs

NF: John Snow and Daenarys Targaryan - The Fi is strong with both these characters

NT: Tyrion Lannister, most likely ENTP with strong developed Fe. One could argue he is ENFP but I think ENTP is more likely.

Now for the SJ and SP types

SJ: Possible Ned Stark, Mr. Standard Honor value guy.

SP: Jamie Bran and also maybe Ayra, pretty much all the good swordsman

Can't spot the INTP on the show but I wouldn't be surprised if it was Hodor.

The more I think about it the possible INTP, I think it could be Ayra, Varyus or Jojen Reed, leaning mostly towards Varyus because of his neutrality. And he doesn't really fit any other mtbi type.