Last night I answered an ad for some old bike parts, the guy said he had taken a bunch of new bikes apart to ebay them 20 years ago and also bought out all the wheels and old parts from a few dealers in his area.

Most wheels are pretty obvious what they came from, lots of chrome steel Ridida rims with Normandy hubs likely from a Peugeot U08 or similar, several new Schwinn S6 wheels off a Varsity or Continental, three sets of Araya aluminum rims with Shimano large flange hubs, a few of the same rims with Normandy hubs, several pair of Weinmann Concave rims with Normandy hubs, and a host of singles, mostly fronts. Then there's two pair of these, Rigida 1320 rims, with Miche and/or Campy low flange hubs with 14ga spokes, and Hutchinson skinwall tires.
There's a handfull of 700c wheels and complete sets, all new or new take offs. there's Weinmann Concave rims with L/F Normanday hubs, a few with Hi Flange Normandy hubs, a few Mavic Open Pro wheels, a few Mavic Super Champion wheels in 27" and a couple sets of various Araya steel rims with Shimano or Sanshin hubs.
These caught my eye because they're super smooth and look ready to go.

Any idea what these may have been taken off of?

Of the top of my head, the only two bikes I remember with these rims were a few Motobecane models and some Trek bikes in the 70's. There are five all together, three fronts and two rear rims. They are either new old stock or new take offs, the vintage tires still have flashing and sprew on the tread .