The wording of your question may have led to assumptions. We've been a target lately and are a little edgy.
Inadvertently rude sometimes, too. Sorry. :welcome:
This "was curious if anyone knew how many BTUs the stock AC was?" implies you have no existing AC unit to have need of a generator.
A word of warning - Be careful using a portable genny, actually any generator, without a carbon monoxide alarm.
Hope the Chap forum has an answer. We can and do help with most things boating, but can be be stumped every once in a while. Let us know what you come up with so we learn from you. :smile: