If it makes you feel any better FJ, I'm in the Irish Australian circles alot because of dancing and I only know ONE Finn, and he's the son of a dancing teacher. There is not one single Finn in Maddy's entire daycare centre, nor her one in Brisbane. You could always spell it as Fionn as well.

There's always Finbar or Fintan as variations too Finbar/Finn/Fintan means 'fair haired'.