Just on from Nerol's excellent advice (as always), if you did want to do an MSc Psychology conversion course there are a few high quality providers who would accept a 2:2 degree. Arden University might be worth checking out, I did mine there and had a great time. Their virtual learning environment is great, and there is a mixture of a blended learning option with 50% time spent on site in say London, leeds, Birmingham or Manchester, or 100% online.
For any provider, check out their Teaching Excellence Framework report which is heavily based on student feedback, readily available online
Marc
Arden University Student Ambassador