Chris Korzen, a self-described flag nerd, was looking for a Maine merchant and marine flag as a gift for a friend in 2013. He wanted something high-quality, done in the nautical tradition, with appliques — 13 on each side, it turns out — sewn onto sturdy cloth. It didn’t exist and he had to have it custom-made by a Connecticut flag-maker. That sparked an idea for Korzen and his wife, Bethany Field, that evolved into, “Why don’t we purchase some equipment ourselves and learn how to make flags? Maybe people will buy them.” That was 2013. Eight years later, yes, people are buying them.