Billy, hand expressing those first few colostrum feeds into a small cup will mean that none is lost in the pump. You should be able to get help to do this, talk it over with your midwife or a breastfeeding councillor.
You really don't need to top up with formula straight away, baby's are designed that colostrum is enough until the full breastmilk comes in. Just because it is possible using a bottle to stuff them full of formula/expressed milk, doesn't mean that it is necessary to do so. They are set up to eat little and often, which is perfect for stimulating your breasts to produce. If they have a tummy full of formula then they won't feel hungry, won't suckle as often and your breasts miss the message that you need to produce more milk.
I totally understand topping up with a small amount of cup fed expressed milk or formula if the baby is taking a while to figure out how to latch, in order to take the edge of hunger so that baby can try again at nursing, so I'm not saying that all top ups are evil, but you don't need to top up as a matter of course if baby is suckling well.
Try reading 'The Womanly Art of Breastfeeding' for lots of advice on how your breasts work, how to hand express etc.
Its worth noting that not all women find expressing possible, this doesn't mean that they don't have enough milk when the baby nurses - it is to do with their let down mechanism not being stimulated enough by the pump.