Rare Lego Mursten box. Where can I sell it and what would I ask?
Your box is a 700/1 Swedish box (a 700/2 doesn't have that much blue space above and below the image).  Value depends on what is inside as well: the bricks/windows/doors, as well as if the interior cardboard partitions are still there.

Also, I know several collectors (with deep pockets) who would be interested if you still want to sell this set.