I went partly down this track a few years ago and 3D CAD modelled up a few of the small parts that would have got lost when the main sight block and peep were removed. Springs are unique too.
They are surprisingly complex little items, must have required quite a few special jigs and fixtures to machine back in the pre-CNC days.

So even IF you possessed all the original drawings they would need to be redrawn to suit modern CNC manufacture referencing off a datum to suit XYZ planes.
Tolerancing is also critically important, without the original figures ideally you would need to measure at least 12-32 ZKK sights to work out where in the Bell Curve of tolerance they lie.
Or they won't fit all ZKKs from all production years!

And if you were going to all that trouble, why not make some improvements like click adjustable windage and/or elevation? The originals were pretty crude in this area and you can waste a LOT of ammo getting on target using the small etched marks.