Just to confuse us further, my vet gave me a bottle of hypertonic saline solution, 7.2% sodium, marked, "for animal use only" and "preservative free". Human saline solution for inhalation is .9% sodium. I've used both, but I have to say that I think I can tell the difference - the 7.2% seems to work better and faster. Though saline doesn't require a prescription, I imagine you'd have to get the animal-strength thru a vet - OP, any chance your vet would mail you a bottle or could you get it from a different, local vet? Since my vet just handed me a bottle no charge, I assume it's not too expensive.
I neb mine with 6-8 cc's of the saline, 2.5 mL/0.5 mL of albuterol sulfate inhalation solution plus, currently, .5 cc's of Gentamycin, an antibiotic. I treat them once per day for about 15-20 minutes and the solution lasts for two treatments, so the mix is for two days - if any was still in the cup after the second day, I'd pitch it and make fresh per my vet. If I was only treating with the Albuterol, I would nebulize them 2-3 times a day as needed. I've not tried just using saline only to nebulize, I always throw in the Albuterol, but I'd be interested in knowing if that seems to help - my boy has plenty of scarring as well and a dry wheeze to boot.