I've made a few variations depending on how you're comfortable printing the ring π.
For example, to print Mario Hat:
ring17_Mario_hat + ring17_Mario_OM
You can also print:
ring19_hat + ring17_Mario_M + ring17_Mario_OM
or:
ring19_hat + ring17_Mario_OM_whl

ring19_hat.stl this is a universal ring, default applies to Wario and Waluigi.

Available to you in the Mario Rings(part3) folder.