I don't remember how long ago they went out of business as a retail store.? A "spin-off" of sorts, Aristo-Craft Trains, lasted longer marketing model railroad equipment which was multiple orders of magnitude larger than our topic-- G Scale!? Aristo-Craft was nominally located in Jersey City for a while (across from Manhattan, I shouldn't assume everyone knows that!) and followed Polk's out of business in 2013.
I see from the post cited below that Polk's was started in 1935.? There are plenty of their ads in early issues of Model Railroader.
(Note: The "spinoff" in the thread leads to a junk domain.? I suppose you know how I know this.)
There is a long thread which started with Polk's and ends, well, I didn't read the whole thing, here:
Cheers,
George (your list-owner)
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