I would say any of the dairy breeds, although I have not kept anglos myself a friend shows them and she says anglos do not give the quantity that her sannans and Togs give.
You would need more than 1 goat as they need company and then once the lambs/kids are weaned do you have a use for the milk ?
belive me once you have milking goats your life changes as you need to plan everything in your life around milking !