Quick search turns up at least three businesses using longer version of the name. Unless this domain has a lot of type-in traffic, I'd try reach out to those shops.
I don't think that gunshops are going to pay more than 3 figures. There is not a lot of demand for gun-related domains and the prices paid are typically in the 3-figure range. And there may be alternatives available for regfee. $300 sounds like the target here, good luck