I'm hoping a native speaker chimes in on this, because I'm not super confident in my translation. But, since no one has yet responded, here's my idea.
I think the top says "Everywhere in the whole country..." and the bottom says "Never without fish" or more literally "Let's work for an endless supply of fish" (하자 means "let's do")
Were you thinking something along those lines?
Hi, thanks for the reply. Yes I have seen a few other posters which often end "Let's do it!" or similar.