After months of searching for the right door and the right window I finally realized I need to change the phrase I used for searching from the arch door into...the gothic door. This time I found a proper door and a proper window almost at once!Here they are:
Found them at Bromley craft. The door needs to be remade into one wing door. And the window - well it is "a bit" too big for the dungeon but since I plan there will be the only one window I think it will be fine.