I went back and found the Julien's auction for the original special build Electroline bass Rick built for John McVie... if for no reason other than a better look at it than this screen capture I had.
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www.juliensauctions.com
I'm a little bit curious about when Rick might have made this bass. It says 80's, so knowing the Electroline idea was a holdover from the Gibson R&D days, that'd be late 80's at the earliest. Granted, Fleetwood Mac wasn't working much at the time, but I can't remember John playing this bass before '04, and I'm not sure about that. I do remember the other Electroline basses,
several actually. I remember the Renaissance basses from The Dance, back in '97. This one though... I'd remember.
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It's quite clearly a modern approach to John's vintage Alembic bass from 1973. Symmetrical-horned body with point, figured maple laminates with some birdseye in them. And... if you zoom in on the nut, it's scalloped. Nice touch, Rick.
At any rate, it appears to be a general pattern that Turner Guitars will build for you having kept the template. There are at least 3 more examples in the world today.