Hmm, I think this is an actively bad idea - if the adventure specifies a particular item that doesn't mean the party can use it; and the presumption in 4e is that the only magic items worth mentioning are useful to the party. So an adventure should preferably use "level X treasure parcel here" - perhaps with a note as to what the origin of the parcel is to hint at a flavorful choice.
You can leave magic item treasure more open, although I would prefer some general suggestions, but for the love of little green d6s, tell us how many copper pieces the ogre had in its burlap sack, how many coins and gems were in the treasure chest, and how hefty was the dragon hoard. The amount of coin a group should receive at a given level is more or less fixed. Just tell us please!
I end up making it all up on the spot and am really bad about writing it down, so I don't have a good feel for how rich my group actually is. I'm working out of a PDF so I can't write it in the margin, although I could go to the trouble of finding every instance of money being found in the adventure and making up some amount, then adding a note to my PDF, but
why should I have to?. I am running a premade adventure to save prep time, and I'm already converting all the monsters to the New Math. It's tedious having to add in treasure as well.
The group reasonably expects practically every single humanoid opponent to have some coins or jewelry of value, and expects at least some other creatures to yield valuable fur, or ritual components, or poison. Tell me the orc chieftan has a rough amber necklace worth 20gp, that the bandit has a sapphire earring worth 120gp and 75 gp in his pouch. Tell me that the carapace of the giant water beetle is used by local villagers to make boats and they are worth 2gp each. Please!
For magic items, I'd prefer some suggestions like "a level 12-13 item suitable for a spellcaster", but that is far less important. Those are something I need to customize anyway. The simple monetary treasure should not be.