While wandering around Madrid, I stumbled upon Casa Hernandez, an alpargateria… Which is apparently what you call an espadrille maker.
They have tons and tons of materials (for custom orders) and shoe style samples in the window.
Once you’re in (after the crazy line), you order (all in Spanish) and try things on. In my case, by showing the clerk pictures of the styles I want and babbling in broken Spanish with lots of hand gestures.
Purchased:
1 pair of denim espadrilles, €5.75
1 pair of black crochet espadrilles, €19.50
1 pair of beige heeled wedges, €25
…crazy.