By and large *flat* nipples pose no problem for a baby. He is born wide eyed and primed to feed on *his* nipples - whatever the size and shape. He doesn't know about the other sorts of nipples out there. In the first hour or so, in the first feedings your baby will "imprint" a sucking pattern.
Babies need to form a part of the breast tissue and nipple into a teat in their mouth. It's not just about the nipples.
Women are extremely anxious about their nipples I find. We clearly all need to sit around together more with our tops off. At one stage I was seeing so many women who were told that their nipples were flat and that was why they had breastfeeding problems that I had to go up to the maternity ward and offer to take my top off so they could see my nipples unless they ceased and desisted passing this message on to women. Because the women I was seeing had perfectly fine nipples - pretty much like mine and everyone elses - not flat at all.
IMO breastfeeding problems are more likely caused by lack of early feeding, lack of skin to skin, drugs in labour etc.
I think an LC visit and an ABA class would be fabulous.
Regarding knitted breasts - my next door neighbour, Beryl, in her 80s is one of aBA's champion titty knitters. She knits boobies (as do a team of other titty knitters around Australia) and they are sold through ABA - check them out at Mothers Direct