You should be familiar with all the major farming dungeons. So it is more a matter of where you can run most efficiently (few potions/good time balance). I'm guessing you blast thru a lot potions to ensure you don't die, so I'll recommend my little run I did around that level: (avoid using any potions during these runs)
Start in KB, head out south down the coast towards the orc lair grabbing any red orchids you find, clear the outer loop of the lair, head back to KB, grabbing any red orchids on the east exit side, then decision time:
1) if you're in good shape, press on into the bandits lair. Main goal here is milk your recoveries/life bar as low as you dare. At least try to clear the wolf cage, as it has decent sellable loot. Recover at inn when you have nothing left
2) Bad shape, rest up, and repeat.
Eventually you'll have a good number of red orchids and instead of a bandit run, head back to Lannegar. Rest, then run the valley to gather as many blue. Trade what you can with Markus for mod potions, then get back to KB and repeat as you like. You save 150 each potion, and can eventually amass enough to head to harder areas and run thru your stash.