Occult Book Dealers of Arkham - for Monophobia's Vengence from Beyond

I ran the three one-on-one Call of Cthulhu (CoC 6th) scenarios Monophobia from unboundbook.org. The three (free) scenarios are excellent and hard to survive, but challenging for an experienced player of CoC.

In one scenario, "Vengeance from Beyond," the Investigator is sent to various occult book dealers and it is left to the GM to invent them. I didn't want to have just a number of standard book dealers, so I decided to make up contacts with more of a Lovecraftian flavor to them.

Here is the list I gave to an Investigator (plus their phone numbers):

Rare book dealers of the occult:
John Cranshaw
Mathilda Mathers
Bishop Telling
Headly Markus
Harry Topus

Some of these people would only meet after being reassured that the inquiry is legit such as having a recommendation from a customer in good standing.

Below are their in-depth descriptions:

John Cranshaw: He doesn't have a store front, but will meet prospective customers only in a public place at a set time. He offers to meet the Investigator in Arkham Central Park at a bench near a specific statue at noon. At the last stroke of noon, ringing from a nearby watch tower, he will mysteriously appear (when the Investigator has looked away or blinked) and will speak to the investigator. Afterwards, he will also mysteriously disappear.

Mathilda Mathers: She doesn't have a store front either. She is a practitioner of the arts. And will meet the Investigator at the Arkham Cemetary at midnight, at an unused part of the cemetery, near a statue. The Investigator will find Mathilda performing a ceremony with candles and a protective circle. In my game, I made her a White Witch. She was renewing a ward against Ghouls.

Bishop Telling: He is the proprietor of Telling Books, an odd basement level bookshop beneath a tannery and butcher shop. The smells are terrible and the liquids that slosh in the gutters questionable. A dirty window provides the only dim illumination in the shop. He has strange customers including cultists interested in his arcane tomes. During the Investigator's visit, there were two strangely swaddled gentlemen browsing the shelves. One will eventually purchase a copy of "The Handbook for The Esoteric Order of Dagon." His fingers, slightly webbed, can be noticed as he drops gold coins on the counter. Bishop wraps the book in plain butcher paper and ties it with twine.

Headly Markus: He runs a salvage operation and sells things found or abandoned at sea. His massive warehouse, on the riverside docks, contains crates and other odd objects under tarps. Various panes of glass are missing from the upper windows and various birds inhabit the rafters. The tarps keep the pigeon and seagull droppings from damaging his already water damaged goods. Dockside activity is noisy and it makes Headly shout in order to be heard.

Harry Topus: He runs Topus Mortuary. His customers are the relatives of people who have run afoul of or summoned dangerous creatures. He handles the remains of people who have been horribly mangled and does a decent job of makeup and stitching. He also handles the liquidation of various occult artifacts and books left behind by the dearly departed who have suddenly left this plane of existence and whose relatives have no wish to deal with said occult items.