Proposed flag (by me) for the Occitan Valleys, based upon:
1.The Occitan Cross (or Cross of Toulouse), in its voidless variant present in the Terra Brigasca, in Pisa, and in other Italian blazons (thus an "Occitan Cross" with Italianity.
2. The colors of the Terra Brigasca, of Liguria/Genoa, and the medieval colors of Turin (all of which are in a white field, a red cross with keys/a bull, etc.). It's worth noting that Old Occitan's linguistic area at one point reached close to the modern cirty of Turin.

3. The colors of Piedmont (principally the colors of Savoy: A white cross in a red field), which, when inverted, match the previous set of colors..
Own adaptation from File:Flag of Occitania (with star).svg
Briantin de Montrei