Contact the NRA?
You can't use an interpreter?
Good idea. That's what I want to do, too. We're trying to schedule it this month.
That's why I think it might be better to use a terp, and make arrangements for the terp to meet ahead of time with the NRA instructor. The terp could explain and demonstrate the interpreting process, make the instructor comfortable with interpreting, and plan the logistics for the training session.
That would also free up the NRA instructor to focus on what he/she would normally do during training.
You want the best instructor and the best interpreter.
If there is an ASL-qualified NRA instructor available, that would be great, especially if you can gather enough deaf participants to fill a class. The instructor might have to travel to your location, or you might have to travel to the instructor's location, which would be extra expense.
Just keep your options open.
Free? That's amazing. What facility do they use for the training? Are there pre-requisites?
I don't think I need anti-terrorism SWAT training but TCS and I are seriously considering this:
Academi Pistol Carbine Overview