Re: PAF in a P90 dog ear cover
No. The closest you can get is am mini-humbucker, which was designed as a direct replacement for the P90.
Standard-size humbuckers are wider than P90's and won't fit under the cover.
And anyway I would think that P90's in a hollowbody would give you a really good jazz tone. Remember that probably most of the jazz records you hear from the 50's and early 60's (and many later) were done with archtops with P90's or P90-like single coils, because prior to 1957 there was no such thing as a humbucker. (Yes, I know Seth Lover came up with it in 1955 but it didn't appear on Gibsons 'til 57.)