Hi. I think it corresponds to Toledo mint (mint marks: M, M with O above, M with T above). Madrid mint worked from 1468 to 1471 (during Enrique IV reign, Isabel was queen of Castille from 1474) and mint-mark M with crown above.
Madrid mint actually began to be operative in 1591 (under Felipe II).
v.
Madrid mint actually began to be operative in 1591 (under Felipe II).
v.





















