@Dazliare p3, p5, and p7 happen to not be THAT different in this particular case (nm LK for lum or lem). If you're concerned, I would do p3 and just plan to do some extra runs.
I might do something like baal/eldritch to lvl 72+, roll acceptable LK map, check racks to make sure they aren't dropping pally shields during this time, go to nm cows till spirit sword and shield base (maybe lum/lem will drop during this), then do a couple hundred nm lk runs for lum for smoke. If you happen on a lem, treachery for merc is always nice, but i would spend it on lawbringer for a5 merc. Hes so nice in hc.
EDIT: you're right, nm cows should give fine exp, and i dont THINK will be too dangerous (I am NOT a HC guy, so take my advice with that grain of salt). So I might even skip baal/eldritch in the sentence above and just get your lvls at cows.
@ddknoll spirit base in hell is just doing wherever there is some monster density. Not nearly as nice as nm cows though, but if you cant give up your current map, then no worries, they will drop eventually. Chaos and pits are always good choices for bases, but anywhere works. My hammerdin was only untwinked till I beat hell baal, so the only LK i did was nightmare Lk for a lum for smoke. I don't know why you would settle for 1 campfire whether running or teleporting though. 2 is always better by a lot. Are you HC? If so i might not use harmony because you lose max block. If you are SC, then ofc why not use it? And i think its +30frw, so thats a lot more than a small charm

Why cant you reroll your current map? If you're going to do more than like a couple hundred LK runs you should definitely roll a decent map for it.