I've certainly seen Mexican folk art cobbler's forms completely covered with Milagros, but I had not seen a painted on before--though have since learned this too is a genre. This is by far the best example I've found, painted with the face of Christ on the toe, and then imagery related to the crucifixion on all sides (nails for the cross, tools of torture, Judas' bag of silver.) Perhaps not for everyone but I really love both the manner of the painting and the specificity of the iconography, very much aligned with the ex voto retablos I love so much. It appears that this was made and sold as a souvenir (recuerdo del bazar), I might guess 1940s or so, and it appears that the cobbler's form is much older than that, with a tin plate on the heel.
9 1/16" l x 3" w x 3 1/2" and in very good condition, with a great patina.