abecedarianmind there are several books out, though biographic, that can give you ideas as well as the mechanics actually used in those days.
The rug item you are asking about is actually being marketed later this year using a more contemporary mode of technology that's less tell-tell than the originals. I don't have the exact dates of release but probably June at the earliest. I'll post more on that item and some other "Victorian" or "Parlor" themed materials being produced through this same source in that said items in question are from my own inventory.
Dale or Allen will probably know the title, but there was a book put out probably 20 some years ago that dealt with the idea of building magic into one's home; secret compartments, thread hook ups, listening devices as well as secret "hot spots" that would allow an accomplice to feed you information without anyone being aware, etc.
Probably the more famous Parlor arrangements I'm aware of, and I do believe they were published, were those associated with the Old Thayer Studio, which happens to be the private home of the Larsen family (both of the late Bill Larsen, Irene and the kids)... these are the folks that made the Magic Castle happen (if you weren't aware of that fact).
You may want to attempt discussion of this idea with James Hamilton of the San Francisco Bay area in that he's done a program that's a complete replica of the original Alexander Hermann program for years. Two other sources would be Norm Nelson (Nelson Magic) and Whit "Pop" Hayden (you can find him through the Scoundrels Forum), they may have some ideas for you on that front.
Something that totally slipped my mind that I should have asked initially, is how formal vs. abstract do you see this project?
My buddy Paul Brook has taken on the mantel of the proper and reserved British Gent. I would imagine, based on our conversations, that his personal goal will be rich wood paneling and lots of books & book shelves. On the other hand you have folks like me, that tend to be more "esoteric" and by nature "pack rats" who have a menagerie of curios; everything from books on the macabre, occult and witchery to artifacts that apparently came from actual Gypsy and Spiritualists parlors; mummified hands, monkey paws, skulls of various sorts as well as wands and of course Seance type devices ranging from a collection of talking boards to enchanted bells, slates and talking horns or tea pots.
Either of these settings fit the Victorian idea, one being dedicated to a more sophisticated "Sherlock Holmes" nature while the other is more akin to Professor Dumbledor's (sp) suit at Hogwarts or perhaps the home of one P.T. Barnum
Should your tastes stray towards the latter, I can assure you that there are many resources about, starting with some of the items you will find at OUTLAW Effects or Lebanon Circle. So enjoy!