Now, I have found Dots N Stripes, an online fabric store based out of Scotland. Dots N Stripes is mostly fabrics for children's clothes, but they had plenty of different ribbing fabrics. I bought their Cerise Pink ribbing and Jersey Fuchsia. I think the colours are a near perfect match.
I just need to pre-shrink the fabric and finish the white T-shirt I was supposed to sew this week!