UK Masters in Law Admissions

I am applying to two-yeat taught masters in law programs (LLM/MA in
Legal Studies) at Bristol, Leeds and Sheffield. These programs are the
only masters degrees that are open to non-law graduates and acceptable
to the Bar Council/Law Society for practicing law in the UK, so that's
the reason I'm applying to them.

My problems are:

1- I graduated from a top Canadian university, but my grades were not
very good. I had a B-average, which probably borderlines on an upper
to lower second-class degree in the UK.
2- I graduated from university six years ago and none of my professors
will remember me, so I can't get an academic reference. I do, however,
have five years of solid work experience and can get good professional
references.

My questions are:

1- What can I do to improve my chances of getting admitted into these
programs?
2- Is it a good idea to try to get in touch with the departments
before applying?
3- Should I try to get an academic reference even if it will be very
shallow?

Thanks.

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