Fitting a recon part may half the cost of the pump - but the labour will be the same - so you'll be paying £650 instead of £850. Is this really the saving you are after? If you want to save a decent amount, then you by the parts to recondition your pump (I don't know how much they are, lets say £50) and do it yourself.
When my transmission had problems I was quoted £3,500 for parts before labour. So I bought the parts to recon it for £150 and learn't which end of a spanner to hold. Its been running fine for the 3 years since. So anyone can fix things themselves if they want to save some money.
There are plenty of threads on here where people have reconditioned their fuel pumps - so there's info on how to do it and people to give you advice before you start and any problems you come across.
Saying "doing it myself is out of the question as i do not have the know how" is not a reason to not do it yourself - it is an often used excuse. If you do not WANT to do it, that is fair enough - you will need to pay someone, what looks to be, fairly close to £850 to do the job.