bonny,
If your "chemist" is in the EU, he should be able to get German formula slow rust solution. A liter has lasted since 1982( I'm not a commercial enterprise) and it works very well for me.
Mike
It cannot be sent via courier, no liquids. Even the uk suppliers such as Dyson will not send bluing solution off the mainland uk. The chemist/pharmacist i used to use was an ancient large animal veterinary practise. Nothing was too much trouble and the people there were professionals, not glorified counterhands.
