There are lots of inexpensive fish to eat, especially when they're canned...tuna, sardines, salmon, anchovies, etc.
Meatless isn't limited to fish either. You can use veggies, cheese, beans, bread, fruit, or buy processed soy products.
For example, I made this soy loaf my wife last night. I dusted it with Plowboys Yardbird rub and coated it with Huff and Puff Competition BBQ sauce. She liked it.