Another WAF trick is to suggest something even bigger, uglier, and more complicated than what you really want. Then "compromise" to what you really wanted.
What makes this more feasible is if you actually own the bigger, uglier stuff -- in the basement or something. When she says, "You don't want to bring THAT in here, do you?!?" you can respond with, "Well, I guess I could live with something smaller... a guy on AK has some speakers about half that size that are supposed to be pretty good..." So you need a "Frankenstein" system with enormous rackmount gear with outboard power supplies. Giant broadcast quality turntable, Ampex 350 dual mono preamps with separate PS, then tube crossovers, giant rackmount tube amps with separate power supplies... you get the idea. With that as your threatening reference point, an all-in-one vintage receiver, even an enormous one, looks tiny by comparison.
When designing our new room, my wife thought for minute that I was planning to install the Jensen Imperials that are currently in the basement. I did nothing to make her think that -- really! -- but it still meant that the Tannoy System 15s (33 x 21 x 18") were not a hard sell. Or another comparison: our local home theater boutique store has these massive McIntosh amps with the biggest meters I have ever seen on home equipment. The amps looked like they were 30" deep, 20" wide, 200 lbs. By comparison, my deHavilland Aries mono amps look completely reasonable!