Getting maniac's prayers

As someone working on a Zubmarine, it’s driving me up the wall getting the number of Maniac’s Prayers I need; does anyone have any tips for getting them more quickly? Right now, I’m just buying primal shrieks, which is both slow and extremely cost-inefficient. Anyone have advice?

Polythreme is probably a good place to get them if you don’t want to collect and convert Primordial Shrieks from Unfinished Business. If you can get your Fascinating and Investigating both up to 7 you can get 130 Maniac’s Prayers, and if you fail to do so by the time your Unnatural Exuberance falls to 1 you’ll still get 65. Also, you can use Thefts of a Particular Character to get Journals of Infamy, which convert into Correspondence Plaques. You may want to do this before leaving for Polythreme if you already have some Casing.

At the very least, getting Primordial Shrieks from Unfinished Business in Ladybones Road (“Debate the Nature of Primordial Shrieks”) should be more effective than buying the shrieks outright. That particular storylet has a reasonably frequent rare success yielding 2.50 Echoes, so it’s not a bad one to grind.