Do Phd or Masters opportunities exist for pharmacy graduates?

They most certainly do especially in the uni of london institute of cancer research

Try the School of Pharmacy at University of Nottingham

is it possible to join a one year MPharm (Hons) for those with a BPharm (Hons)?

As far as we can tell it is not posible to skip any years of the MPharm degree. Try the Royal Pharmaceutical Society of Great Britain web site for information. They have to approve all MPharm courses in the UK.