Hi Craig, i can see why that bass would be hard to let go it’s a beauty. As for the headstock repairs, you may or may not know that alembic have a history of repairing those kind of bass injuries before they started making their own instruments, and it’s one of the reasons the point became part of the design for the body on their basses. It was to encourage musicians to use stands. From my years on the forum i get the feeling that existing owners are less concerned about buying damaged headstock basses like yours when the repair has been done by alembic themselves.
But i sincerely hope you get your custom build. When you get some ideas, the “Dreaming for now “ section is great place to hash them out. However i confess that after years of ownership i still can’t finalise a custom specification for myself. I still live in hope 😇