WI: A Third Wife for D. Felipe IV

In 1651, after the birth of the Infanta Margarita Teresa, the queen of Spain, D. Mariana of Austria, was ill and took a long time to recover from the birth (according to the Velasquez bio I'm reading at the moment, Velasquez was supposed to paint her when he returned from Rome, but due to her illness, was given a commission to paint her step-daughter, the future queen of France instead).

So, let's give Mariana a prod, maybe the Spanish doctors do one too many blood lettings, and she dies shortly thereafter. After a suitable period of mourning, Felipe IV has to marry again. Who or where does he marry? La Grande Mademoiselle is often mentioned, but France and Spain are still at war in 1651/1652, so I'm guessing that that's pretty unlikely. The logical candidates (Eleonora Maddalena Gonzaga and Anna de Medici) are both married already, which means we might get a reasonably "foreign" queen for Spain?
I've been looking some more, and the new queen of Spain is going to be more foreign (ie unrelated to Felipe IV) than any seen since Élisabeth de Valois (which I'm guessing won't be a bad thing).

  • No Habsburg archduchesses available (last possible train (Isabel Klara) left the station in 1649).
  • No half-Habsburg princesses available (Mariana was Felipe's only niece; and both of Ferdinand III's sisters either didn't have daughters, or they died in infancy).
  • Which means we're down to quasi-Habsburgs (the descendants of Felipe's parents' siblings):
  • Isabel Clara Eugenia (his elder paternal half-aunt): no issue
  • Catalina Miguela (his younger paternal half-aunt): two sons who left issue, daughters married into various Italian dynasties):
    • Margherita Violante (b.1635) or Enrichetta Adelaide (b.1636) of Savoy. Enrichetta's cutting it fine since she married in 1652, so that leaves Margherita Violante.
    • Luisa Cristina of Savoy-Carignano (b.1627) - only married in 1654 OTL.
    • Gonzagas: no issue
    • Estes: Isabella (b.1635) or her aunt, Anna Beatrice (b.1626)
  • Magdalene (his mother's younger sister), married the grand duke of Tuscany. No girls available in the 1650s
  • La Grande Mademoiselle
Maybe Caterina Farnese, the daughter of Odoardo Farnese? She'd certainly be religious enough for the Spanish court. IIRC while he father dabbled with a French alliance he was more or less neutral in the Franco-Spanish war but he's probably too focused on redeeming the Duchy of Castro to put forward any kind of dowry for Caterina.

One outlier candidate I'd add would be Joana, Princess of Beira (still alive in 1652) or maybe her younger sister Catherine of Braganza. Such a match would require Philip to make peace with her father John IV and recognize Portuguese independence, which in 1652 is highly unlikely, but in the long run it would be a great boon to Spain. They could cut a detail that allows them to retain not just Ceuta but Tangiers and Olivenza and a favorable border between Brazil and the Viceroyalty of Peru. More importantly it frees up huge numbers of troops and resources to fight France and to suppress the Catalan revolt. It also links an independent Portugal to Spain rather than allowing it to form alliances with England and France as it did OTL. Sadly it's unlikely that Philip and the Spanish court would see it that way as interesting an idea as it is.