Ship and Sail in Fort Walton Beach sells new Hunter 340 and 380 models with <50 foot masts. They get them custom built from the Hunter factory.I have a 380 with the short mast. I am very happy with my performance. I believe the taller mast is prettier than mine. There is a picture of mine in the owner photo album of this web site. I am guessing that modifying one would get expensive because it would require new stays, shrouds and modified sails. There are still some "50 foot" bridges I can't get under(Destin, FL comes to mind).