Originally Posted by PUDDLE JUMPER II
So the photos are of my Deck
stepped Mizzen mast stainless steel
tabernacle, and sitting on top of it is a chunk of aluminum, with 4qty through bolted screws holding the two piece together. Is their a name for this Aluminum Slide that the mizzen slides over by chance?
The plate + hinge pin(s) is usually called a "mast hinge", or a "hinged mast plate assembly" or a "hinge assembly for a mast step", the latter often being clumsily abbreviated to the noun stack of "mast step hinge assembly".
With few exceptions, the hinged mast plate assembly is specific to a particular mast section (the mast extrusion) and to some corporation that manufactured what your boat
The bigger chandleries (e.g. West Marine) once carried some of the common hinged mast plate assemblies for trailer
sailers. Rig-Rite lists a couple of generic hinged mast plate assemblies - none of which look similar to yours (see: https://www.rigrite.com/Spars/SparParts/Mast_hinges.php
I think that means you have your choice of fabricating a replacement or looking at yacht wreckers or finding the original source of your equipment