Using Braeburns at £1.28/kg, I got 375ml from 0.740kg, so you get 0.5mL per gram. This means that 1L of Braeburn apple juice would cost £2.52 per Liter. That is quite a bit! Actually more than some pear juices. The juice was tasty, clear, tasting slightly like cider (farm-yardy/earthy).
Royal Gala, my personal favorite. Price of £1.18/kg. From 0.48kg, I got 325mL. That £1.75 per Liter. That's half the price of Braeburn and it is a much sweeter juice, it looks slightly pink, but maybe does not have such a strong apple flavour.