My friend takes Theology and Religious Studies at Univ of Bristol. I know it's not just Religious Studies like you were looking for but she seems to have covered a wide range of religions in first year and is concentrating on Buddhism in her second year with only one module on Christianity.
It's probably best to just check all theology/R.S courses, you might find that they modules available to you are fairly flexible. I'd have thought that R.S is one of those subjects were the course can have the same name at several universities but completely different structures/topics/objectives.