I would have thought that in your country, you should be able to find any number of cheap panamas at a local market in summer. Mine was about £30 after haggling. If I can find one in such a market in England, surely it should be possible in Spain! It won't be the finest of weaves, of course, but for day to day use it will hold up perfectly well, and you won't care when it inevitably falls into the river or the sea and returns to you sopping wet & misshapen (the M&S one I have has been christened thus in several seas around the world over the years; I'm always surprised about how easily it can be returned to a decent shape as it dries!)
BTW, I agree with all of what AAS has said about your seersucker jacket today.
I agree with the general thrust of your point, but there would be a bit more of a visual difference from the side or from behind. My other panama is snapped up at the back, and looks a bit more rakish from those angles than the one I posted yesterday (it also has a slightly lower crown which adds to that overall impression). I tend to wear it with more casual outfits whereas the one with the turned down brim and higher crown seems to work better with tie/jacket looks IMO. I do also find that the turned-down rim keeps the sun off the nape of my neck a bit better but that may be more of a psychological than practical effect as I doubt that the shadow really extends that far down.