Patience. The fact you have heard nothing yet means nothing. Most posters have more to do than monitor the board 24/7. It may take time, but you will get a response, I'm sure. I assume your need for large shoes is not because you are going barefoot.
You've tried Casa Nelson in Puerto Plata? Thye carry they typical fare worn by the locals plus some imports. I was able to by equivalent to size 13 there.
I buy all shoes online. For me, for kid and for mi esposo. I just pick styles that 0.5 size difference wont hurt in case shoe runs small or big. I mostly buy from amazon or ebay. Only once shoe was too big but it was just 15$ so thats ok. Or buy brands that you know they are true to the size.
Lucas: I go where my daughter tells me to go...always buy my sneakers at good places on sale and I only own two pairs of "shoes". Some Bass Weegens (penny loafers) and some black dress shoes. Not like the old days back in the 50s when I would go to Winthrop Shoes on Madison Ave and spend 125 $$ on a pair of pebble grained dress shoes (one piece leather) or 200 on a pair of cordovans...Of course they lasted me through college and into my first years of living here...Best shoes I ever owned outside of a couple of pair of Timberlands.