I'll be in central London on the day of the Hungary game. Happy to make it down to the Famous Three Kings.
I believe the Tartan Army used to meet in the Albion at Blackfriars, but they stopped showing Scotland games when it went to Premier Sports, so I don't know if there'll be a significant number in there. Would be good for me if they were, as it's walking distance of where I'm staying.
I'd also be curious to know if there was anywhere in North London where you'll likely find a few Scottish fans.