I think this is classed opalescent not opaline glass.
If it was a souvenir from Sacre Couer would it be more likely to have a religious emblem/design on it probably of the church?
But thinking along those lines though, perhaps Sr. du S. C. de Montmartre is a short for Souer du Sacre Couer de Montmartre?
So it may have belonged to the sisters perhaps. Is that a possible?
I also think it's Bohemian

The enamelling design, the base yellow enamel and the way it's made cut at the top with no pontil mark.
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