If a job is advertised with a salary range, unless it says that the appointment will be made at the bottom of the scale "except in exceptional circumstances" (which you see with some project-funded post doc jobs), I would assume that the institution has the money to pay at the top of the range if they think it is appropriate.
I work at a Russell Group uni, and the figures you give split across salary bands, so it may be that the lower end is for people who are PhD-pending. We wouldn't appoint someone without a PhD higher than that (unless they had lots of other experience), but would make a commitment that they would automatically move up as soon as they received their PhD. We would be unlikely to appoint lower if someone already had a PhD.
If you want to negotiate, you need to give a reason why you are worth more. I don't think your travel costs would be considered a good reason unless you are working in London. Good reasons are generally related to your previous experience and what you would bring to the institution.
It can be useful to look at the role description for the grade above and note the parts you are already meeting, e.g. publications, research funding, and use that to argue that you should be nearer to that grade, i.e. nearer the top of the advertised grade.
There has been no final decision on portability at the moment, so if you have good REF-able publications that can be a good basis for negotiation.