I hope you are just joking, because it is safe to say that what you are planning to do is almost impossible, and for sure meaningless.
1. You cannot buy the K1000 drivers separately. Even fifteen years ago AKG were out of stock of them and the drivers were unobtanium. I saw them sold only once on the second-hand market over the course of fifteen years. Sure, you can buy a working pair of the AKG K1000 and get the drivers, but it would cost you about half the price of a used/refurbished pair of the Mysphere.
2. No store sells the Mysphere without the drivers. The only place where you can get is the manufacturer itself. But I highly doubt they would sell it to you. And even if they would, the Mysphere without the drivers combined with a pair of the K1000 would cost you more than a used/refurbished pair of the Mysphere.
3. Both the Mysphere and the K1000 are not usual headphones which you can simply open, unscrew the driver and put the driver in a diffrent cup or frame (like Grado).
This square plate IS the driver of the K1000. The membrane is not removable. It is glued to the plastic frame.

The same can be sad about the Mysphere. Its frame was specifally made for this exact unique driver. You cannot fit anything else in there. No other driver will fit, least of all the driver of the K1000.