I don't think men and women would have equivalent salaries in the Mad Men universe.
In europe this is still very common.
Europe is a big place.
I think you need to modify this to "in some part of" or even in "many parts of".
Where I come from this is extremely uncommon.
Labour force participation rates by sex:
USA: 70.2% for men, 57.7% for women.
Europe (OECD countries): 79.7% for men, 62.6% for women.
So it's more common in EU for women to work than their sisters in the US, but the gender difference in participation rates is also higher in Europe.