the faa does not set any weight or height requirments to fly  as long as you can fit in the cockpit.  but this is only for the faa  the max and minimum vary from company to company  for example vermont air national gaurd max is 77 inches which is about 6,5
what id do is check for the possible schools and acadamys you might attend.
and remember the world of avation is constantly improving its aircraft for technology and comfort for the pilot. there is always hope.
good luck
-jimmy