The OTC purchase of Neosporin in the the UK is forbidden. The substance is a mix of Zinc Bacitracin, Polymixin B and Neosporin Sulphate, all of which are not permitted for sale as far as UK pharmacies are concerned.
Whilst there are some circumstances under which the antibiotic cream may well be useful, it's as well to remember that its indiscriminate use contributes to bacterial resistance to antibiotics throughout the world. Currently in the USA, there is a variety of MRSA that has led to limb amputation in some patients and the FDA are putting it down to indiscriminate use of Neosporin ointment, which can readily be bought in grocery stores and drugstores.
Yes, Neosporin ointment and variants can be purchased on ebay etc, but I think you need to remember that the reason the antibiotics contained in the product have largely fallen into disuse is because they have been shown to be nephrotoxic and neurotoxic to humans. Acceptance of this toxicity is greater in the UK than in the USA at present and unfortunately, this is one of the reasons why back-door imports of the stuff are available.
In the USA, the public are literally taking their life in their hands by applying this stuff to every graze, pimple and boil. I work in the US for a few weeks every year and I have first-hand experience of the how the stuff is regarded over there. Be very careful.