Lab ammonia
I had the same problem trying to find ammonia. I thought that I had found it in a hardware shop after many visits to other places. The label said that it was a 9.5% solution with water. When I got the stuff home and opened the bottle, it looked the same colour as methylated spirits, so bells started to ring and I didnt use it. I'm lucky enough to be working beside a horticulturl lab, so I asked the labtec if he had any pure ammonia. He was only too happy to given me a free bottle of 50% ammonia/water solution (its good stuff).
So if you know anyone who works in a lab and your looking for ammonia the chances are that they will have some.