I usually think of 'post-metal' as being pretentious tools who think of themselves somehow as 'thinking men' and form bands like Tool or Isis.
I say this as a 46 year old PhD who can appreciate Hellhammer and Venom.
Yeah, those guys are the ones that are being pretentious. :?
If you like the Gibson Dirty Fingers sound, why don't you just try one of those? I know this is the BKP forum, but that doesn't mean it's forbidden to try other brands. Similar types of pickups might be the Dimarzio Super Distortion, or perhaps the Distortion or Invader from Seymour Duncan.
I would look for a pickup that has plenty of high end definition for the subtleties and clean parts, enough mids to cut through but not boosted mids because that might sound too 'vintage' and ample but tight bass, because the tuning and thick strings give enough bass themselves and too much added bass from the pickup might sound muddy or flubby.