Can't it simply be a merchant ship of some kind? They are usually big and brawny and capable of long voyages.
She can certainly serve in a related capacity. There's logic (IMO) in the idea that as she and her fleet of ships make their way down the coast, selling their wares along the way before finally making their home port, that she would serve as cargo hold for the needful things she got in trade and sale.
I don't know if it matters to your story, but a wooden fishing vessel would be REALLY stinky. A merchant ship could smell like anything, really, depending on what they traded for. Spices?
It would matter insomuch as the setting, yes. @big soft moose jokes about naughty goings-on below-decks, but a sunburned tumble amongst sacks of binnie seeds with their bright, citrus smell is certainly worth describing.
...well, old dead fish might add atmosphere as well...depending on how scaly (or slippery) they like it. Woo hoo!!!
