Unless this is going to be a repeat job, I would look at having the sheet material water-jetted for your circles.
Circle shears are very common for prepping material for metal spinning. They can be expensive, and for a one-time job, may not be worth it. Not to mention they are wasteful of material...typically you shear a sheet down to various size squares, approximately 1/8" wider & longer than the circle you will cut, then trim the circles.
That is why I said have them water-jetted...no Heat Affected Zone to F&^% up a spun part, and they can be nested effectively, yielding more parts per sheet.