Hiya FG. It does sound like a great system, and I was going to give it a go with my firstborn but my DH wasn't as motivated as me to take part.
I'm going to suggest you wait a couple of weeks before you start because that's valuable time for you and baby to learn how to breastfeed. Feeding from the bottle is much easier for bubs than the breast, so beware that you may have a baby who doesn't transfer from bottle to breast without a fuss.
I have a hand pump that was passed on to me from a relative. I have found it sufficient in the past for getting enough milk for when I needed it (when going out or whatever). If you are only giving her one feed of ebm per day then you'll probably find the hand pump sufficient. You could even try hand expressing (without a pump) first to see if that works for you before shelling out for a pump.
I've heard that the TT bottles are great. I've also heard that Pidgeon make a teat that's got a cross-shaped hole in it that aparently imitates the flow of milk from the breast pretty well.
Don't know anything about sterilisers though, sorry. I have always just used milton.
GL!