I am an international student, and did my MA in the UK. It's definitely pretty rare to get funding for overseas students. I got admission to a couple of great places, but no funding. Here's what one of my potential supervisors (who was also my MA supervisor) said regarding funding: Since the Government in the UK has cut back grants even more radically this year (while pretending that there are more) I think there is little hope of getting one anywhere in the UK. But some universities (though not UEA) do have private funding, so you might be lucky.
Oxford and Cambridge probably fall in to the category of universities that have private funding.
Regarding teaching experience, it's pretty rare. I have friends doing their PhDs now and if they do get experience it's mostly as Tutorial leaders or tutors, never anything more than that. You certainly can't create and teach your own course, which is something the programs I've got admission to in the US all allow you to do.