So this is the solution I've come up with. It seems to work really well so I thought I'd share.
First get yourself a cheap vest top. I've found some in charity shops for as little as 50p, but if you prefer to buy new you can find lots on eBay for under £5
Try your top on and mark on the front with chalk where your nipples are. Draw a 4" vertically, extending 2" above and 2" below the point of the nipple. You may want to make this line bigger depending on the size of your boobs, experiment to see what works best for you.
Cut along the chalk marks with fabric scissors and then sew with a zig-zag stitch along the open edge to prevent fraying. Sew backwards and forwards a few times at the top and the bottom of the slit to prevent the fabric laddering or splitting vertically.
Now pair your vest with a matching cardigan. I recommend something with a high round neckline rather than a v-neck because it's more likely to cover the holes. Keep it mostly buttoned up and just unbutton and pull aside to breastfeed - simple as that!
Thanks for reading!
Love and luck LL x
Love and luck LL x