"You could buy 32 in the Pharmacy in Tesco and another 2 packs of 16 with your shopping."
That's rather surprising, because I often find that at the checkout, the checkout person is usually very aware of the supply and limitation of paracetamol. Unless there is a possibility that the supply obtained from the pharmacy is bag wrapped and perhaps pre-paid?.
I am glad that you mentioned Co-Proxamol (Kapake), because I was on them as a repeat prescription, and due to a stomach problem, I was stopped using them. I had supplies of Co-Codamol 30/500ml (30ml codeine phosate/500ml paracetamol), but again these were discontinued due to the same stomach problem, the same applied to Aspirin.