From a fundamental information theory standpoint, it's can't exist*. For secure voting you need to identify the voter and ensure the voter's ballot is included in the final count. The real problem is that you have to do it in a way that not even the voter can identify their ballot in the list of counted ballots. This is necessary to prevent coerced voting. The only way we can do this is by putting ultimate trust in some part of the system. The primary goal when designing voting system is to make that trusted part as small and as simple as possible. All the things you would need to do to make this is work over the internet is diametrically opposed to both those criteria.

That said, you can absolutely design a very inexpensive, easy to use, secure, computerized voting system if you wanted to. It consists of terminals powered by an Arduino, a basic LCD screen and cheap thermal printer. You can have whatever ballot layout (along with any assistive technologies) and the voter makes their selections electronically. The printer prints a voter-verifiable ballot using the same ballot that is mailed to absentee voters. It's put in the same box as the other votes. A scan and counting machine power by another Arduino counts the ballots and displays the number of votes for each candidate/measure.

Ultimate trust is placed in the code and hardware of the counting machine. While that is fairly complex, it is entirely possible to verify it's operation to a reasonable degree of certainly. If you really wanted to be sure, I could design a counting circuit out of fully viable mechanical relays. Plus you can always just hand recount or run them through machines from a different manufacture.

* Theoretically something called homomorphic encryption might be able to solve this, but we have no working implementation and it massively violates criteria number 2.

It's possible the rivet head you see in picture 3 is the top of a post that goes into the back casting, but I think it's there to hold the stack of lamination that make up the stator together. I suspect the stator is just pressed into the casting. You may have to make a custom tool to remove it.

I would suggest getting a short section of pipe that fits freely over the stator and rests on the edge of the back casting. You would place a plate on top of the pipe and it would have 4 holes for threaded rods that would go in between he coils. The threaded rods would have projections that would reach under the outer sections of the stator and lift it out as you tighten the 4 nuts evenly.

Another possibility is to chill the whole thing in a freezer, then quickly heat the outside casting with a couple of torches and it may expand enough to just fall right off. This often works great for getting bearing races out of aluminum housings, but this one kind of looks like cast iron to me. You don't have the difference in expansion coefficient working for you, so you have to heat the outer part quickly before the heat penetrates to the inner piece (and you have to be careful not to damage it).