Piekielnik is a village in the administrative district of Gmina Czarny Dunajec, within Nowy Targ County, Lesser Poland Voivodeship, in southern Poland, close to the border with Slovakia. It lies approximately 19 kilometres (12 mi) west of Nowy Targ and 68 km (42 mi) south of the regional capital Kraków.
Google maps - tinyurl/y96td8r; put http: before the address
It would be safer to change 'Parafia s. Jacobi' to 'Parafia św. Jakuba Apostoła' to make sure that a polish mailman will deliver the letter to the right place.
Have a look at the site - tinyurl/y9tdhk4; put http: before the address