Those thin walls are a killer! Meshmixer thinks the maximum dimension of the model is just under 43 mm, although the alternative indication is that it's slightly smaller than 43 inches. What is the true diameter? What program did you use to create the model? How thick is the dome? What is the airspeed velocity of an unladen swallow?

Certainly, 3D printing is a good method to use for prototyping, although for thin enough material, one could create a buck, a forming device and hammer aluminum or steel sheet to create the dome, adding a 3D printed clip, but that's outside the scope of this forum.

If it is necessary to chop the disk up into quarters rather than halves, the thin portion of the dome will create a weakness. If cleats, also known in the radio control world as doublers are used, the dome gets thicker where they are attached. It can be unsightly, but strong. It appears that an internal cleat/doubler would be invisible in your design and provide the necessary strength for the prototype.

I sure hope that thing isn't 43 inches diameter! I can print up to about 8" with a good bit of luck, but would still segment the disk and tilt it to get a better fit on the print bed. The re-assembly would require a bit of sanding on a true surface but the results are likely to be acceptable for a prototype. Printing in ABS would make for a strength improvement, and allow for acetone smoothing. Acetone smoothing would also hide some of the glued joints if carefully assembled.

A challenging project, to be sure.