At least that's my understanding of excise taxes for an individual.
Maybe as a business, you could apply that $200 towards the cost basis of the firearm to reduce the profit if you sell it. Just blue skying though. That's a question for an accountant.
Kicking it around , if the underlieing item itself were eligible to be a deductable business expense , it might be able to be included that way. Consult your tax advisor.