The NRA will be fine. They have millions of members who pay not only for the benefits but because they are politically invested in the organization and are glad to give money, gun sales are still twice what they were in the Bush years, the gun confiscation movement is failing to win over popular opinion among young people, and a much more friendly Court is on its way that will strike down more needless laws.
You obviously didn't even skim the article, because if you did you'd find that the reason they are in trouble is that they "cannot access financial services essential" and they "lost insurance coverage — endangering day-to-day operations," not because a reduction in sales. This is because of the good work of the state of New York and the successes they've had to make sure that no one in the financial sphere is willing to due business with these merchants of death.