Search around and see if there are any adaptations that might work. I have a recollection that some have used the newer rotors on the earlier car albeit with alterations. In the long run it may be cheaper even if new calipers are needed. But, yes, if people with early cars find acceptable rotors in wrecking yards GRAB THEM!
A while back I found a very nice set at a Pick Your Part 50% off sale. They were $8 each. So many times I'll go to the wrecking yard, a swap meet etc. not only with the mentality of what I need now..., but also what I might need in the future as well. I've actually had people stop me and tell me, "That's what I should be doing." That can be encouraging when your lugging around items that get heavier by the minute --- for some date far into the future. Even if I never wind up using a part I often gain a profit when I sell it off.