Clothing stores for average Americans (XL Europeans)

My wife and i are here for a few weeks (actually we're in San Sebastian until the 29th so i take suggestions here too)... I love Madrid fashion. The flowing clothing, scarves, etc however I'm around 108kg with broad shoulders.

I tried an XL jacket at Zara and it "fit" but it was simply too small in the shoulders and across the back.

Is there anywhere in Madrid (or San Sebastian) you know of with American sized clothing but Madrid style?

Any help appreciated. Thank you.