No midwife or bf consultant is going to actually advise you to get a 'just in case' bit of formula in - they cannot by law (? or govt policy, same thing?!) undermine the promotion of bf-ing.
Bottles and a pump v useful if you might want to express so that you can have nights out / nights off etc. in due course.
Stop here if you might cave to the 'temptation' of the formula if you have it in the house...
However, having gone home from hosp on a Sunday a month ago when my baby was 1 day old, sleepy and placid, yet was still up at 4am after 9 hours solid screaming which was not remotely satisfied by a few mls of colostrum, I was going mental. We looked at every bf website under the sun, looked up advice for "the first few days" in all our books, and tried all the NHS bf consultant phone numbers ("thank you for calling. our office hours are...")
I was sobbing in a corner. We called the lovely lovely midwife on the birthing centre where I'd delivered (Northwick Park, brilliant brilliant brilliant) and she virtually whispered down the phone "do you have any formula?" No, but there's a 24hr garage nearby.
Yes we agonised for another 15 mins or so about how much of an abject failure that would make me (precisely the opposite of the exclusive bf-er and totally sorted yummy mummy I planned to be) but my dp couldn't face the sight of me shaking with distress and the sheer decibels that can be produced by such a little person
It is all going to be about what you know about how strong your resolve is. We used some formula again in the first week on particularly painful occasions - I had cracked and bleeding nipples, and on one side I even got a blister which lasted a few days and was agony! - but I expressed for as long / as much as we ff-ed so that the 'demand' mmessages were going in even if the supply was not yet coming out.
I don't think I've used FF at all since my strapping boy was a week old. He lost 4oz off his 9lb5oz birth weight in that first week but was 9.12 at just under 3 weeks, so I'm convinced that a little bit of nasty anti-earth-mother powder did him no harm and my sanity a massive favour.