A simple Ross corrector would produces only mediocre visual results over the field size required. This variation uses different glass types and acts in a slight compression mode. It needs a mild Hyperboloidal Primary to achieve useful but not brilliant results. The glass types are a little unusual but certainly available. Unfortunately, the lenses are large thin meniscii.
Performance is excellent.
The last option uses three separate elements of standard glasses in conjunction with a Paraboloidal primary mirror. Performance is excellent. Because the lenses are single elements, there exists the option of working stock catalogue lenses into the design. The last PlanoConvex lens is a standard Edmond catalogue item and the deep meniscus element may be produced by modifying an M Griot stock catalogue lens. Modifying the M Griot lens so as to utilize the convex surface would be an interesting exercise.