It depends on the vintage. HSH Silhouettes have come with at least two different sets of humbuckers over the years. Possibly three or four. I do not know about the middle single coil.
My HSH Silhouette is from 1996 and it came stock with PAF Pros back then. The middle single coil model was not identified. They all sound great in that guitar.
At some point they switched the stock humbuckers to virtual PAFs. That is what is currently listed on the EBMM page for the Silhouette:
https://www.music-man.com/instruments/guitars/silhouetteGiven that those pickups are listed as no longer in production on Dimarzio's website, it is either the case that (i) the EBMM website is incorrect and needs to be updated or (ii) Dimarzio still makes those pickups, but only as OEM for that guitar. If the former is the case, they might come with 36th Anniversary PAFs instead now.
To further complicate things, I seem to remember them coming stock with PAF Classics for a while, but I could be mistaken. The PAF Classics are also no longer in production.