While toying around with hwdata, I've seen that systool -b pci tries to use /usr/local/share/pci.ids rather than the /usr/share/misc/pci.ids file that sys-apps/pciutils installs. It's your call whether to make it depend upon pciutils or not. There's also the option of waiting till we see if we get to use hwdata instead :)
let's wait, sysfsutils are pretty much dead development wise, so let's wait and see what happens. Please keep me informed.
sysfsutils isn't going anywhere, closing this out.