I can't recall if anyone has actually done one.
The PATB-1b seems to be the Parallel Axis take on a Custom 5 [hotter, but with extended treble due to coil architecture, higher inductance, lower string pull, and softer attack that is extremely responsive to pick articulation]. Not precise, no confirmation from Seymour Duncan, and the wind may not be identical, but it is 15.7K of 43AWG, and a lot of people have noticed resemblances to various models of the Custom.
PATB-3b is the Parallel Axis inspired by the '59 Bridge.
So a hybrid of the two ought to be similar to a Parallel Axis version of the '59 Custom Hybrid. Can't know for certain without trying it, of course.
IIRC, someone did and liked a PATB-1b/PATB-2b hybrid, for a tangential factoid.