Cloth Seal, Mary I, Alnage, Crowned M

Cloth Seal, Mary I, Alnage, Crowned M, Image & Held by Mike Patrick.
From Ebay, 17mm.

Crowned M // missing but markings on large rivet stub

Possibly a cipher of Mary I.
From Mike Patrick, "The 'Crown over M' on the Mary shilling of 1553 (image attached) looks a bit hopeful."

See BSG.CS.01951.