I've also found it called Broxol on eBay.com.au - but it's an equine product and the listing doesn't give concentrations.
According to the manufacturer’s website the concentration is 5mg/gram of product. See here.
Given that the studies used doses between 60mg and 420mg three times a day, that would pretty much obliterate the 750g pot in a few days. However these were studies undertaken for Parkinson’s disease, the cough dose is much lower. So even if I don’t have a fundamental problem swallowing horse medication, I am not sure that this is really helpful.
On top of that the price of the 750g pot on the manufacturer is about 2/3 the price from that on eBay, however it doesn’t include postage.