The model number "BTXL-6000-00" are imprinted on the nut, so it was easy to identify once I compared the measurements against GraphTech's spec sheet. The measurements of the nut currently on the guitar are commensurate with those listed on the site:
Measure Length Width Height E to E
inches 1.735" 0.196" 0.329" 1.425"
mm 44.07mm 4.98mm 8.36mm 36.20mm
It's clearly the wrong fit. The first pic shows the nut sticking out from either side...

... and doesn't quite reach the truss cover...

... and a view of the truss cover from above.

I know the width based on specs is supposed to be 1 11/16", but I cannot seem to locate the remaining specs. It looks like something that will have to be cut fresh as opposed to something pre-cut and stock from GraphTech, but I'd like to give my tech a heads-up on the dimensions if anyone has them.
Lastly... check out the fading on the face of the headstock - looks kinda silvberbursty!

Thanks, all.