Last year I was running a Swords & Wizardry campaign and found that half of the players elected to be clerics or paladins. That caught me flat-footed. All I had prepped was a standard dungeon crawl so I downloaded three of pundit’s adventures: The Child Eaters, The Secret Order of the Red Lady, and The Defilers. All are good fodder for lawful characters looking to root-out some evil heresy in a medieval setting.
Although I didn’t actually run them, they are well-written and worth the price. Compared with other OSR adventures I’ve purchased, these are less about combat and more about diplomacy and investigation. They include a general situation and details about the relevant NPC’s and their motivations. How players approach the situation is wide-open. There is no predictable sequence, no rails. That may or may not be what you want.
The Child Eaters may be a bit edgy for some (there is nothing metaphorical about the title). Know your group :-)