I dont know if those are stock for that car but they do look like a typical for the drum era. What changed and usually kills you for discs is that extra big step where the valve stem is. Not sure why they made them that way but when the went to discs they made that step much smaller or even eliminated it.
I did a swap a few years ago from Scarebird. That is the company that sells you brackets and tells you what to buy. I just took my spare tire to the parts store and asked to see a rotor and caliper. I looked like it was going to be very close so I figured I would be able to make it fit if it didnt. Turns out it did fit. The caliper had just enough angle on the outer part to clear that extra step in the wheel. I was in about the same situation as you. I was told the stock wheels would not clear but had a feeling that mine were not stock. I never did figure out what the wheels came off of. Many makes made slight changes sometimes even year to year when they were making the disc transition.