PP...The D'Addario heavies which I mentioned above are 14-59. Any decent shop should be able to get them for you. Many shops won't sell them to you because they think you'll string them to standard pitch on a lightly built guitar and then cause problems with repairs and warranty concerns. For tuning down they're the real deal, but make sure the nut is cut for them and a general set-up is done.

Peace, Mooh.