I am on the larger side too, and was especially large when my milk came in & I wanted to feel "secure"...........so I know how you feel.

We are a retail desert up here in Darwin so Target was my only option, and although they weren't underwired, I think the Hestia brand that they stock was great! Plain white, easy maternity hooks and nice and firm feeling.

Bear in mind, that when you are BF, your nipples may not get very erect ever (mine never did). Also for the first few months you may need breast pads, so your nipples are not evident anyway.........