Richard, that thing looks fine and I commend you for making something that works to solve this annoying issue. Well done!
Steve, you are right... except that Rig-Rite apparently know they are an exclusive supplier for Kenyon spars and others because their prices are astronomical (alumimum mast step casting, $265-- should be $65. Complete boom assembly for my boat, over $750 plus $250 shipping, when I could drive 4 hours and pick it up-- DAMCO have one for $595. And don't get me started on their prices for old-gen Schaefer halyard stoppers. Sheesh.)