Well, I'm thinking of setting aside the items from White loop that can be sold or upconverted to items that can be sold to the Rat-Market. So Vital Intelligence, Oneiromantic Revelations for Parable, and Extraordinary Implications for Uncanny Incunabulum (though this one is a hassle to upconvert since you need Connected: Benthic as well and is only a small portion of the reward of going from node 4 to 3 so maybe it's not worth the extra actions). Hoard and sell them to the Rat-Market during the right week then convert all the shillings to Maniac's Prayer. When the Engineer needs Correspondence Plaque, upconvert your Maniac's Prayer as needed and get easy Emetic Revelations. This should effectively allow you to do more White loop before needing a Black loop to top-up your Emetic Revelations.