I wouldn't label it historical fantasy either. To me, the first word is the more significant--historical fantasy is so called because the historical setting is crucial to the telling of the story. Not just window dressing, but that the story couldn't be set in any other time. We don't know enough about this story--I could say the mobile phone bit could be handled in a variety of ways, and as for currency, just move to France! <g> But then again, perhaps you're writing a mystery and that pound note is absolutely central.
If you look at other entries in historical fantasy, you'll see what I mean. The historical part is front and center. Then again, urban fantasy is more than just fantasy set in a city. It has to be modern and it nearly always includes fantastical creatures like werewolves and vampires. Something like Peter Beagle's Folk of the Air isn't going to be labeled urban fantasy.
Can you get away with simply calling it fantasy?