Most of the Japanese sedans from the mid 80-90's have IRS, and use relatively straight forward bolting arrangements. That may or may not be true for the European sedans, aka BMWs, which have in my opinion more complicated rear IRS. But its what you can think to weld/bolt to your car.
I've seen one or two 510-200sx, 280zx rear IRS attached to Datsun 510 wagons (originally solid axle).
I'm thinking 90's Nissan Maxima, 280 zx, might be good, or the late 80's toyotas.
But go look at what's in your local JY, crawl underneath a few, and take a tape measure and some ideas about how its going to bolt to your car. Same answer for front.
Now if you find a good donor, but say the front shock set up is too tall, look at other cars from the same maker, to find a similar front strut that is shorter. Most car makers re-use parts, or at least bolt patterns and bolt sizes, so many times the front shock from a Honda civic fits an Acura Intgra, and vise verse (and so on for datsun/nissan, toyota)
Dudes Ex Machina:
https://www.facebook.com/dudesexmachina?Everyone who has ever built anywhere a 'new heaven' first found the power thereto in his own hell- Frederick Nietzsche