Do granicy z Polska to jest bardzo blisko stad. I tak to je to možliwe. Jak maly ten nasz świat jest./To the border with Poland it is very close from here. And so it is possible. How little this our world is.
We have very pretty website, which is able to find nearest shops to you: https://pripravky-na-inkontinenci.heureka.cz/f:12224:24728,24734/, and its far more than just Tena.
My tip for hardest country is North Korea. There is reason, which differ this place from even poorest african countries, is that all people, who can need them are rejected from society and sentenced to die in camps for disabled people.
Easiest i think, is US. There are reachable in every wallmart, and US have too bigger range of them, and some are far better than european ones. I am always pretty angry, when i know, that stretchy type of diapers, are in US common, but in EU very rare.