I just happened to come across an ad for an earlier version (made out of angle aluminum)

From the Jan/Feb 1982 Hobie Hotline:

"The Sailing Systems 'Organizer' - New!"

"Locks to mast base of Hobie 14, 16 or 18 by the use of a single push pin. Attach all the rigging on the mast including trapeze wires, halyards and shrouds in an organized fashion. No more tangled line and wires when trailering. Saves wear and tear on the mast and on your nerves! Complete with push pin."

Part No. 175, $19.95 (that's about $50 in today's money)